ISO/FDIS 965-6

ISO general purpose metric screw threads — Tolerances — Part 6: Limits of sizes for internal and external threads (fine and medium tolerance qualities, first and second choices)

This document specifies the limits of sizes for the major, pitch and minor diameters of ISO general purpose metric screw threads (M) conforming to ISO 261 having basic and design profiles in accordance with ISO 68-1. This document is applicable to the metric fastening screw threads with the ten recommended tolerance classes specified by ISO 965-1.

Filetages métriques ISO pour usages généraux — Tolérances — Partie 6: Limites de tailles pour les filetages intérieurs et extérieurs (qualités de tolérance fines et moyennes, premier et second choix)

General Information

• Status: Not Published
• ICS: 21.040.10 - Metric screw threads
• Technical Committee: ISO/TC 1 - Screw threads
• Drafting Committee: ISO/TC 1 - Screw threads
• Current Stage: 5020 - FDIS ballot initiated: 2 months. Proof sent to secretariat
• Start Date: 22-Apr-2025
• Completion Date: 22-Apr-2025

Standards Content (Sample)

FINAL DRAFT
International
Standard
ISO/TC 1
ISO general purpose metric screw
Secretariat: SAC
threads — Tolerances —
Voting begins on:
2025-04-22
Part 6:
Limits of sizes for internal and
Voting terminates on:
2025-06-17
external threads (fine and medium
tolerance qualities, first and second
choices)
Filetages métriques ISO pour usages généraux — Tolérances —
Partie 6: Limites de tailles pour les filetages intérieurs et
extérieurs (qualités de tolérance fines et moyennes, premier et
second choix)
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
Reference number
FINAL DRAFT
International
Standard
ISO/TC 1
ISO general purpose metric screw
Secretariat: SAC
threads — Tolerances —
Voting begins on:
Part 6:
Limits of sizes for internal and
Voting terminates on:
external threads (fine and medium
tolerance qualities, first and second
choices)
Filetages métriques ISO pour usages généraux — Tolérances —
Partie 6: Limites de tailles pour les filetages intérieurs et
extérieurs (qualités de tolérance fines et moyennes, premier et
second choix)
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
© ISO 2025
IN ADDITION TO THEIR EVALUATION AS
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
or ISO’s member body in the country of the requester.
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ii
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Limits of sizes . 1
4.1 General .1
4.2 Internal threads.3
4.3 External threads . 39
Bibliography .72

iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 1, Screw threads.
A list of all parts in the ISO 965 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
FINAL DRAFT International Standard ISO/FDIS 965-6:2025(en)
ISO general purpose metric screw threads — Tolerances —
Part 6:
Limits of sizes for internal and external threads (fine and
medium tolerance qualities, first and second choices)
1 Scope
This document specifies the limits of sizes for major, pitch and minor diameters of ISO general purpose
metric screw threads (M) conforming to ISO 261 and having basic and design profiles in accordance with
ISO 68-1.
This document is applicable to the metric fastening screw threads with the ten tolerance classes (4H, 5H, 6H,
7H, 6G, 4h, 6h, 6g, 6f and 6e) recommended in ISO 965-1.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 965-1, ISO general purpose metric screw threads — Part 1: Principles and basic data
ISO 5408, Screw threads — Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 5408 apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
4 Limits of sizes
4.1 General
The limits of sizes specified shall be derived from the fundamental deviations and tolerances specified in
ISO 965-1.
The limits of sizes for major, pitch and minor diameters of screw threads (M) have been calculated by the
following formulae, derived from the formulae provided in ISO 68-1 and ISO 965-1, and rounded to the third
decimal place.
Internal thread:
Major diameter D = D + EI
min
Pitch diameter D = D + EI = D – 0,649 519 P + EI
2,min 2
D = D + T
2,max 2,min D2
Minor diameter D = D + EI = D – 1,082 532 P + EI
1,min 1
D = D + T
1,max 1,min D1
External thread:
Major diameter d = d + es
max
d = d – T
min max d
Pitch diameter d = d + es = d – 0,649 519 P + es
2,max 2
d = d – T
2,min 2,max d2
Minor diameter d = d + es = d – 1,082 532 P + es
1,max 1
d = d – 0,866 025 404 P/2 + 2 C
3,max 1,max max
d = d – T – 0,866 025 404 P/2 + 0,250 P
3,min 1,max d2
Where es is a negative value.
For the symbols and their definitions see ISO 965-1.
The maximum major diameter of internal thread D is not specified.
max
Usually, the minimum major diameter of internal thread D and the maximum minor diameter of external
min
thread d are gauged by the crest diameter of GO thread gauges in accordance with ISO 1502.
1,max
For external threads, controlling the maximum minor diameter d and the minimum root radius R
1,max 1,min
ensures the conformity of the maximum minor diameter d .
3,max
Whether to measure the maximum and minimum minor diameters of external thread, d and d , shall
3,max 3,min
be decided according to the relevant threaded product documents. Unless specifically defined otherwise, it
is not necessary to carry out a measurement of the minor diameter d .
For the ten tolerance classes and nominal diameter ranges see Table 1.
Table 1 — M screw threads with the ten recommended tolerance classes
Nominal diameter
Screw thread Tolerance class Table number
mm
4H From 1 to 100 Table 2
5H From 1 to 300 Table 3
Internal thread 6H From 1,4 to 300 Table 4
7H From 3 to 200 Table 5
6G From 1,4 to 200 Table 6
TTabablele 1 1 ((ccoonnttiinnueuedd))
Nominal diameter
Screw thread Tolerance class Table number
mm
4h From 1 to 100 Table 7
6h From 1 to 100 Table 8
External thread 6g From 1 to 300 Table 9
6f From 1,6 to 200 Table 10
6e From 3 to 200 Table 11
4.2 Internal threads
Limits of sizes for the internal threads with tolerance class 4H shall be as specified in Table 2.
Table 2 — Limits of sizes for the internal threads with tolerance class 4H
Dimensions in millimetres
Major diam-
Nominal diam-
Pitch diameter Minor diameter
eter
eter Pitch
a
D P D D D D D
min 2,max 2,min 1,max 1,min
1 0,2 1,000 0,910 0,870 0,821 0,783
1 0,25 1,000 0,883 0,838 0,774 0,729
1,1 0,2 1,100 1,010 0,970 0,921 0,883
1,1 0,25 1,100 0,983 0,938 0,874 0,829
1,2 0,2 1,200 1,110 1,070 1,021 0,983
1,2 0,25 1,200 1,083 1,038 0,974 0,929
1,4 0,2 1,400 1,310 1,270 1,221 1,183
1,4 0,3 1,400 1,253 1,205 1,128 1,075
1,6 0,2 1,600 1,512 1,470 1,421 1,383
1,6 0,35 1,600 1,426 1,373 1,284 1,221
1,8 0,2 1,800 1,712 1,670 1,621 1,583
1,8 0,35 1,800 1,626 1,573 1,484 1,421
2 0,25 2,000 1,886 1,838 1,774 1,729
2 0,4 2,000 1,796 1,740 1,638 1,567
2,2 0,25 2,200 2,086 2,038 1,974 1,929
2,2 0,45 2,200 1,968 1,908 1,793 1,713
2,5 0,35 2,500 2,326 2,273 2,184 2,121
2,5 0,45 2,500 2,268 2,208 2,093 2,013
3 0,35 3,000 2,829 2,773 2,684 2,621
3 0,5 3,000 2,738 2,675 2,549 2,459
3,5 0,35 3,500 3,329 3,273 3,184 3,121
3,5 0,6 3,500 3,181 3,110 2,950 2,850
4 0,5 4,000 3,738 3,675 3,549 3,459
4 0,7 4,000 3,620 3,545 3,354 3,242
4,5 0,5 4,500 4,238 4,175 4,049 3,959
4,5 0,75 4,500 4,088 4,013 3,806 3,688
5 0,5 5,000 4,738 4,675 4,549 4,459
5 0,8 5,000 4,560 4,480 4,259 4,134
a
Refers to the imaginary coaxial cylinder through the endpoints of straight flanks.

TTabablele 2 2 ((ccoonnttiinnueuedd))
Major diam-
Nominal diam-
Pitch diameter Minor diameter
eter
eter Pitch
a
D P D D D D D
min 2,max 2,min 1,max 1,min
5,5 0,5 5,500 5,238 5,175 5,049 4,959
6 0,75 6,000 5,598 5,513 5,306 5,188
6 1 6,000 5,445 5,350 5,067 4,917
7 0,75 7,000 6,598 6,513 6,306 6,188
7 1 7,000 6,445 6,350 6,067 5,917
8 0,75 8,000 7,598 7,513 7,306 7,188
8 1 8,000 7,445 7,350 7,067 6,917
8 1,25 8,000 7,288 7,188 6,817 6,647
9 0,75 9,000 8,598 8,513 8,306 8,188
9 1 9,000 8,445 8,350 8,067 7,917
9 1,25 9,000 8,288 8,188 7,817 7,647
10 0,75 10,000 9,598 9,513 9,306 9,188
10 1 10,000 9,445 9,350 9,067 8,917
10 1,25 10,000 9,288 9,188 8,817 8,647
10 1,5 10,000 9,138 9,026 8,566 8,376
11 0,75 11,000 10,598 10,513 10,306 10,188
11 1 11,000 10,445 10,350 10,067 9,917
11 1,5 11,000 10,138 10,026 9,566 9,376
12 1 12,000 11,450 11,350 11,067 10,917
12 1,25 12,000 11,300 11,188 10,817 10,647
12 1,5 12,000 11,144 11,026 10,566 10,376
12 1,75 12,000 10,988 10,863 10,318 10,106
14 1 14,000 13,450 13,350 13,067 12,917
14 1,5 14,000 13,144 13,026 12,566 12,376
14 2 14,000 12,833 12,701 12,071 11,835
15 1 15,000 14,450 14,350 14,067 13,917
15 1,5 15,000 14,144 14,026 13,566 13,376
16 1 16,000 15,450 15,350 15,067 14,917
16 1,5 16,000 15,144 15,026 14,566 14,376
16 2 16,000 14,833 14,701 14,071 13,835
17 1 17,000 16,450 16,350 16,067 15,917
17 1,5 17,000 16,144 16,026 15,566 15,376
18 1 18,000 17,450 17,350 17,067 16,917
18 1,5 18,000 17,144 17,026 16,566 16,376
18 2 18,000 16,833 16,701 16,071 15,835
18 2,5 18,000 16,516 16,376 15,574 15,294
20 1 20,000 19,450 19,350 19,067 18,917
20 1,5 20,000 19,144 19,026 18,566 18,376
20 2 20,000 18,833 18,701 18,071 17,835
20 2,5
...

ISO/TC 1
Secretariat: SAC
Date: 2025-03-0604-08
ISO general purpose metric screw threads — Tolerances — —
Part 6:
Limits of sizes for internal and external threads (fine and medium
tolerance qualities, first and second choices)
Filetages métriques ISO pour usages généraux — Tolérances — Partie 6: Dimensions limites pour filetages
intérieurs et extérieurs (qualité de tolérance fine et moyenne, premier et deuxième choix) — Tolérances —
Partie 6: Limites de tailles pour les filetages intérieurs et extérieurs (qualités de tolérance fines et moyennes,
premier et second choix)
FDIS stage
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication
may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying,
or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO
at the address below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
EmailE-mail: [e-mail]
Website: www.iso.org
Published in Switzerland
© ISO #### 2025 – All rights reserved
ii
Contents
Foreword . Error! Bookmark not defined.
1 Scope . Error! Bookmark not defined.
2 Normative references . Error! Bookmark not defined.
3 Terms and definitions . Error! Bookmark not defined.
4 Limits of sizes . Error! Bookmark not defined.
4.1 General . Error! Bookmark not defined.
4.2 Internal threads . Error! Bookmark not defined.
4.3 External threads . Error! Bookmark not defined.
Bibliography . Error! Bookmark not defined.

iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of
ISO documentsdocument should be noted. This document was drafted in accordance with the editorial rules
of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights
in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s)
which may be required to implement this document. However, implementers are cautioned that this may not
represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 1, Screw threads.
A list of all parts in the ISO 965 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
© ISO #### 2025 – All rights reserved
iv
FINAL DRAFT International Standard ISO/FDIS 965-6:2025(en)

ISO general purpose metric screw threads — Tolerances — —
Part 6:
Limits of sizes for internal and external threads (fine and medium
tolerance qualities, first and second choices)
1 Scope
This document specifies the limits of sizes for major, pitch and minor diameters of ISO general purpose metric
screw threads (M) conforming to ISO 261 and having basic and design profiles in accordance with ISO 68-1.
This document is applicable to the metric fastening screw threads with the ten tolerance classes (4H, 5H, 6H,
7H, 6G, 4h, 6h, 6g, 6f and 6e) recommended in ISO 965-1.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 965--1, ISO general purpose metric screw threads — Part 1: Principles and basic data
ISO 5408, Screw threads — Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 5408 apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— — ISO Online browsing platform: available at https://www.iso.org/obp
— — IEC Electropedia: available at https://www.electropedia.org/
4 Limits of sizes
4.1 General
The limits of sizes specified shall be derived from the fundamental deviations and tolerances specified in ISO
965-1.
The limits of sizes for major, pitch and minor diameters of screw threads (M) have been calculated by the
following formulae, derived from the formulae provided in ISO 68-1 and ISO 965-1, and rounded to the third
decimal place.
Internal thread:
Major diameter D D = D + EI
min min
Pitch diameter D = D + EI = D – 0,649 519 P + EI
2,min 2
D = D + T
2,max 2,min D2
Minor diameter D = D + EI = D – 1,082 532 P + EI
1,min 1
D = D + T
1,max 1,min D1
External thread:
Major diameter d d = d + es
max max
d = d d = d – T
min max min max d
Pitch diameter d = d + es = d – 0,649 519 P + es
2,max 2
d = d – T
2,min 2,max d2
Minor diameter d = d + es = d – 1,082 532 P + es
1,max 1
d = d – 0,866 025 404 P/2 + 2C 2 C
3,max 1,max max max
d = d – T – 0,866 025 404 P/2 + 0,250P250 P
3,min 1,max d2
Where es is a negative value.
For the symbols and their definitions see ISO 965-1.
The maximum major diameter of internal thread D maxDmax is not specified.
Usually, the minimum major diameter of internal thread D D and the maximum minor diameter of
min min
external thread d are gauged by the crest diameter of GO thread gauges in accordance with ISO 1502.
1,max
For external threads, controlling the maximum minor diameter d and the minimum root radius R
1,max 1,min
ensures the conformity of the maximum minor diameter d .
3,max
Whether to measure the maximum and minimum minor diameters of external thread, d and d , shall be
3,max 3,min
decided according to the relevant threaded product documents. Unless specifically defined otherwise, it is not
necessary to carry out a measurement of the minor diameter d .
For the ten tolerance classes and nominal diameter ranges see Table 1Table 1.
Table 1 — M screw threads with the ten recommended tolerance classes
Nominal diameter
Screw thread Tolerance class Table number
mm
4H From 1 to 100 Table 2Table 2
5H From 1 to 300 Table 3Table 3
Internal thread 6H From 1,4 to 300 Table 4Table 4
7H From 3 to 200 Table 5Table 5
6G From 1,4 to 200 Table 6Table 6
4h From 1 to 100 Table 7Table 7
6h From 1 to 100 Table 8Table 8
External thread
6g From 1 to 300 Table 9Table 9
From 1,6 to 200 Table 10Table 1
6f
© ISO #### 2025 – All rights reserved
Nominal diameter
Screw thread Tolerance class Table number
mm
From 3 to 200 Table 11Table 1
6e
4.2 Internal threads
Limits of sizes for the internal threads with tolerance class 4H shall be as specified in Table 2Table 2.
Table 2 — Limits of sizes for the internal threads with tolerance class 4H
Dimensions in millimetres
Major
Nominal
Pitch diameter Minor diameter
diameter
diameter Pitch
a a
D P D D D D D D
min min 2,max 2,min 1,max 1,min
1 0,2 1,000 0,910 0,870 0,821 0,783
1 0,25 1,000 0,883 0,838 0,774 0,729
1,1 0,2 1,100 1,010 0,970 0,921 0,883
1,1 0,25 1,100 0,983 0,938 0,874 0,829
1,2 0,2 1,200 1,110 1,070 1,021 0,983
1,2 0,25 1,200 1,083 1,038 0,974 0,929
1,4 0,2 1,400 1,310 1,270 1,221 1,183
1,4 0,3 1,400 1,253 1,205 1,128 1,075
1,6 0,2 1,600 1,512 1,470 1,421 1,383
1,6 0,35 1,600 1,426 1,373 1,284 1,221
1,8 0,2 1,800 1,712 1,670 1,621 1,583
1,8 0,35 1,800 1,626 1,573 1,484 1,421
2 0,25 2,000 1,886 1,838 1,774 1,729
2 0,4 2,000 1,796 1,740 1,638 1,567
2,2 0,25 2,200 2,086 2,038 1,974 1,929
2,2 0,45 2,200 1,968 1,908 1,793 1,713
2,5 0,35 2,500 2,326 2,273 2,184 2,121
2,5 0,45 2,500 2,268 2,208 2,093 2,013
3 0,35 3,000 2,829 2,773 2,684 2,621
3 0,5 3,000 2,738 2,675 2,549 2,459
3,5 0,35 3,500 3,329 3,273 3,184 3,121
3,5 0,6 3,500 3,181 3,110 2,950 2,850
4 0,5 4,000 3,738 3,675 3,549 3,459
4 0,7 4,000 3,620 3,545 3,354 3,242
4,5 0,5 4,500 4,238 4,175 4,049 3,959
4,5 0,75 4,500 4,088 4,013 3,806 3,688
5 0,5 5,000 4,738 4,675 4,549 4,459
Major
Nominal
Pitch diameter Minor diameter
diameter
diameter Pitch
a a
D P D D D D D D
min min 2,max 2,min 1,max 1,min
5 0,8 5,000 4,560 4,480 4,259 4,134
5,5 0,5 5,500 5,238 5,175 5,049 4,959
6 0,75 6,000 5,598 5,513 5,306 5,188
6 1 6,000 5,445 5,350 5,067 4,917
7 0,75 7,000 6,598 6,513 6,306 6,188
7 1 7,000 6,445 6,350 6,067 5,917
8 0,75 8,000 7,598 7,513 7,306 7,188
8 1 8,000 7,445 7,350 7,067 6,917
8 1,25 8,000 7,288 7,188 6,817 6,647
9 0,75 9,000 8,598 8,513 8,306 8,188
9 1 9,000 8,445 8,350 8,067 7,917
9 1,25 9,000 8,288 8,188 7,817 7,647
10 0,75 10,000 9,598 9,513 9,306 9,188
10 1 10,000 9,445 9,350 9,067 8,917
10 1,25 10,000 9,288 9,188 8,817 8,647
10 1,5 10,000 9,138 9,026 8,566 8,376
11 0,75 11,000 10,598 10,513 10,306 10,188
11 1 11,000 10,445 10,350 10,067 9,917
11 1,5 11,000 10,138 10,026 9,566 9,376
12 1 12,000 11,450 11,350 11,067 10,917
12 1,25 12,000 11,300 11,188 10,817 10,647
12 1,5 12,000 11,144 11,026 10,566 10,376
12 1,75 12,000 10,988 10,863 10,318 10,106
14 1 14,000 13,450 13,350 13,067 12,917
14 1,5 14,000 13,144 13,026 12,566 12,376
14 2 14,000 12,833 12,701 12,071 11,835
15 1 15,000 14,450 14,350 14,067 13,917
15 1,5 15,000 14,144 14,026 13,566 13,376
16 1 16,000 15,450 15,350 15,067 14,917
16 1,5 16,000 15,144 15,026 14,566 14,376
16 2 16,000 14,833 14,701 14,071 13,835
17 1 17,000 16,450 16,350 16,067 15,917
17 1,5 17,000 16,144 16,026 15,566 15,376
18 1 18,000 17,450 17,350 17,067 16,917
18 1,5 18,000 17,144 17,026 16,566 16,376
© ISO #### 2025 – All rights reserved
Major
Nominal
Pitch diameter Minor diameter
diameter
diameter Pitch
a a
D P D D D D D D
min min 2,max 2,min 1,max 1,min
18 2 18,000 16,833 16,701 16,071 15,835
18 2,5 18,000 16,516 16,376 15,574 15,294
20 1 20,000 19,450 19,350 19,067 18,917
20 1,5 20,000 19,144 19,026 18,566 18,376
20 2 20,000 18,833 18,701 18,071 17,835
20 2,5 20,000 18,516 18,376 17,574 17,294
22 1 22,000 21,450 21,350 21,067 20,917
22 1,5 22,000 21,144 21,026 20,566 20,376
22 2 22,000 20,833 20,701 20,071 19,835
22 2,5 22,000 20,516 20,376 19,574 19,294
24 1 24,000 23,456 23,350 23,067 22,917
24 1,5 24,000 23,151 23,026 22,566 22,376
24 2 24,000 22,841 22,701 22,071 21,835
24 3 24,000 22,221 22,051 21,067 20,752
25 1 25,000 24,456 24,350 24,067 23,917
25 1,5 25,000 24,151 24,026 23,566 23,376
25 2 25,000 23,841 23,701 23,071 22,835
26 1,5 26,000 25,151 25,026 24,566 24,376
27 1 27,000 26,456 26,350 26,067 25,917
27 1,5 27,000 26,151 26,026 25,566 25,376
27 2 27,000 25,841 25,701 25,071 24,835
27 3 27,000 25,221 25,051 24,067 23,752
28 1 28,000 27,456 27,350 27,067 26,917
28 1,5 28,000 27,151 27,026 26,566 26,376
28 2 28,000 26,841 26,701 26,071 25,835
30 1 30,000 29,456 29,350 29,067 28,917
30 1,5 30,000 29,151 29,026 28,566 28,376
30 2 30,000 28,841 28,701 28,071 27,835
30 3 30,000 28,221 28,051 27,067 26,752
30 3,5 30,000 27,907 27,727 26,566 26,211
32 1,5 32,000 31,151 31,026 30,566 30,376
32 2 32,000 30,841 30,701 30,071 29,835
33 1,5 33,000 32,151 32,026 31,566 31,376
33 2 33,000 31,841 31,701 31,071 30,835
33 3 33,000 31,221 31,051 30,067 29,752
Major
Nominal
Pitch diameter Minor diameter
diameter
diameter Pitch
a a
D P D D D D D D
min min 2,max 2,min 1,max 1,min
33 3,5 33,000 30,907 30,727 29,566 29,211
36 1,5 36,000 35,151 35,026 34,566 34,376
36 2 36,000 34,841 34,701 34,071 33,835
36 3 36,000 34,221 34,051 33,067 32,752
36 4 36,000 33,592 33,402 32,045 31,670
38 1,5 38,000 37,151 37,026 36,566 36,376
39 1,5 39,000 38,151 38,026 37,566 37,376
39 2 39,000 37,841 37,701 37,071 36,835
39 3 39,000 37,221 37,051 36
...