Hersey Controls 2 Complete Valve Kit PN: 65543 for FRP-II Blackflow Preventer Replacement parts for FRP-II Low Pressure Blackflow Preventer PN: 65543 Complete Valve Kits Includes: First Check Valve Assembly Second Check Valve Assembly Relief Valve Assembly Case Gaskets (2) Check Valve O-ring (2) Relief Valve O-ring Check Valve Mounting Screws (8) New surplus. Powered by SixBit's eCommerce Solution. This item is in the category "Business & Industrial\Other Business & Industrial". The seller is "surplusmeisters" and is located in this country: US.