This part of ISO 2725 specifies dimensions, the designation and the marking of machine-operated “impact” square drive sockets with operating end having a hexagonal or double hexagonal form in accordance with ISO 1174-2. Hand-operated sockets are dealt with in ISO 2725-1. NOTE 1 Machine-operated “impact” square drive sockets are listed under number 2 2 02 01 0 in ISO 1703. NOTE 2 The figures in this part of ISO 2725 are given only as examples. They are not intended to influence the manufacturer's design.