OS & Y Type Bolted Bonnet Gate Valve The OS & Y Type Bolted Bonnet Gate Valve is engineered for reliable flow control in industrial applications. Its Outside Screw and Yoke (OS & Y) design ensures precise stem positioning, enhancing operational safety and visibility. The bolted bonnet provides a secure seal, minimizing leakage risks and allowing easy maintenance. Built from high-strength materials, it offers excellent resistance to pressure and temperature variations.