Precision molded in polypropylene that is reinforced with fiberglass for additional strength. The Self-aligning ball moves freely against the PTFE seats for smooth operation. The valve opens and closes with very little pressure on the handle. Ball is diamond turned, after molding, to make it spherically perfect, which provides precise contact between ball and seats. PTFE self-lubricating stem bushing and seats cannot stick or bind. FKM seals. 3" valves have a maximum pressure rating of 100 psi. 2-1/2" ball thru hole opening.