A tight connection is possible when you choose this replacement S-Pump Valve Adapter. Made of durable materials, the component offers top quality for all applications. This adapter is designed for use with all S-Series vacuum pumps and generators. Teflon tape is not recommended for the threads, vacuum is sealed on the duckbill valve’s built-in O-ring. The use of Teflon tape can cause damage to the fitting or the duckbill valve.