... PTFE Coated Stem: SS Seat: PTFE Our PTFE lined butterfly valve adopting the PTFE butterfly boardto sealed spherical surface, being ... rubber on the rotry base between the butterfly boardand valve seat, therefore, the impact and beautiful outlook,reasonable ... strong alkaline, aquaregia, etc.Type of connection: counter connection, flange connection.Applicable temp: Actuator: Hand Lever, Worm Gear, Electric ...