This International Standard applies to attachments for hand-operated square drive socket wrenches listed in ISO 1703 under designations 5 1 00 03 0, 5 1 00 04 0, 5 1 00 04 1 and 5 1 00 05 0.NOTE 1 The above-mentioned designations correspond to the former designation numbers 203, 204 and 205.It specifesa) the overall dimensions,b) the minimum Rockwell hardness value for their driving squares,c) the method of torque testing,d) the minimum torsional strength values,e) designation, and f) marking.NOTE 2 For the specifcation of square adaptors with a hexagon or cylindrical fat drive, for power socket wrenches, see ISO 3317.