The NIBCO® ductile iron gate valve provides full flow with minimal pressure drop. The NIBCO® flanged ductile iron gate valve is designed to be the main control valve in an automatic fire sprinkler system. The resilient wedge, ductile iron gate valve features Class 125 flanged, flat face end connections for easy installation and accessibility. Outside screw and yoke (OS&Y) gate valves are recommended when positive shutoff and a quick visual indicator of open/closed position is required. This valve features a pre-grooved stem for tamper switch mounting and is drilled, tapped, and plugged at location "A" for bypass. It is listed by Underwriters Laboratories of the US and Canada (UL/ULC) and FM Approved.