Part Number: 71670. #9 socket (70860) is for 5/8″ (16mm), #10 socket (70880) is for 11/16″ (18mm), #11 socket (70900) is for 3/4″, #12 socket (71700) is for 7/8″ (22mm) and #13 socket (71720) is for 1″ (25mm).