BS 3643-2:2007 ISO metric screw threads. Specification for selected limits of size (incorporating corrigendum No. 1)
Specifies the fundamental deviations, tolerances and limits of size for tolerance classes 4H, 5H, 6H and 7H for internal threads and 4h, 6g and 8g for external threads for coarse pitch 1mm to 68mm diameter, fine pitch 1mm to 33mm diameter and constant pitch 8mm to 300mm diameter.
Supersedes BS 3643-2:1981. Came into effect 30 November 2007. First published June 1965. Second edition, December 1966. Third edition, December 1981. Fourth edition, November 2007. Amendment C1 dated June 2014 - See Foreword.
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