Superior Tool 03960 4-Way Key-Fits Stopcocks, Sillcocks, and Valves-Steel Construction for 1/4"-9/32" and 5/16"-11/32 Internal Square Heat-treated steel. Sizes 1/4" - 9/32" and 5/16" - 11/32" internal square. Fits stopcocks, sillcocks and valves Heat-treated steel Sizes: 1/4&#034; 9/32&#034; 5/16&#034; 11/32&#034; internal square