4" Wafer Check Stainless Steel with Viton Seat 150/300# design Dual Disc Titan CV44SSV4" Wafer Check Stainless Steel with Viton Seat 150 300# design Dual Disc Titan CV44SSV Resilient Soft Seats Minimal Head Loss Quick Closure to Reduce Water Hammer VITON PROPERTIES: Offers a broad range of chemical resistance and excellent heat resistance. Good mechanical properties and compression set resistance. Often used in applications where nothing else will work. Fair low temperature resistance and limited hot water resistance and shrinkage.