Posi Lock offers hands-free hydraulic bench vise Posi Lock's patent-pending hydraulic vise (PHV859A and PHV859M) is rated at five tons with 8" wide jaws that open to 8". Hydraulic pressure closes the jaws and a spring opens them. The foot controlled pump has advanced hold and retract features along with an air speed control valve to close the jaws quickly or slowly for additional safety. The vise operates at a press in either vertical or horizontal positions. It is available with a manual foot pump or air over hydraulic foot pump.