Plate size: 85mm x 85mm (1 gang, 2 gang & 3 gang). Plate size: 145mm x 85mm (double with 13A socket). Plate size: 85mm x 85mm (1 gang & 2 gang). Plate size: 145mm x 85mm (3 gang & 4 gang). G&H Brassware are a UK manufacturer of high quality switches and sockets.