ISO 4762
ISO 4762 - Hexagon socket head cap screws
Hexagon socket head cap screws with metric coarse pitch thread, product grade A. The screw is driven by a hexagon key seated in a socket sunk into a plain cylindrical head, so the head can be buried in a counterbore and nothing stands above the surface; this makes it the usual fastener of machine tools, jigs, moulds and dies. A size is the pair d x l: the thread diameter fixes the head diameter dk, the head height k, the socket size s and the key engagement depth t, while the length decides whether the screw keeps a plain shank or is threaded up to the head. The reference thread length b of the table is 2d + 12 mm and applies only to lengths above the full thread limit of that diameter. Covers threads M1,6 to M64 with nominal lengths 2,5 to 300 mm. Its German predecessor DIN 912 was replaced by DIN EN ISO 4762; the fine pitch counterpart is ISO 12474.