Tighten knurled knob by hand or use 1/4" drive ratchet
Tool is designed to relieve clamp spring pressure in very tight spots. Vise is often left in place, with the clamp compressed, during service. Tool is 3" long and opens to 1 1/2". Ramp on jaws guides tab of clamp into correct position and traps it in the slot for safety. Tighten knurled knob by hand or use 1/4" drive ratchet.