Fabri-Valve C/F134R/S bonneted knife gate valve is used in difficult services to provide high cycle stem sealing and superior stem seal containment. The cylindrical packing around the stem provides a tighter, easier to maintain stem seal. Bonneted valves are available with an optional metal backseat on the stem. In addition, the valve can be supplied with a gate wiper and purge ports in the bonnet to minimize movement of material into the bonnet. If a non-pressurized dirt shield is required, specify a Figure 37 w/dirt shroud. Standard body materials include Figure 304, 316 and 317L stainless steel. Special alloys such as 254 SMO^®, Hastelloy C are also available.