Versa pioneered modular directional control valves, in which a variety of standard bodies, spools, and actuators can be assembled in thousands of ways to meet virtually any valve application. This concept, coupled with Versa's patented "anti-extrusion" arrangement of "O" ring seals, leak-proof, rugged forged and solid-rod construction, small residual volumes, testing before shipment, quick delivery, and worldwide service has made Versa a leading name in air valves