ISO 1085:2016 specifies the size pairing of double-ended wrenches with unequal nominal widths across flats.

NOTE The wrenches covered by this document are those identified in ISO 1703:2005 under reference nos. 1 1 01 02 0, 1 1 02 03 0, 1 1 02 04 0, 1 1 02 05 0, 1 1 02 06 0, 1 1 02 08 0.