2-Way -Cast Bronze Bodies, Velvetrol® Internal Piston Pilot Operated Solenoid Valves, Normally Closed or Normally Open - Full Port, Manual Open & Adjustable Closing Speed Controls, Class F or N coils are waterproof, fungus proof, molded of filled polyester with 18" leads in NEMA 1 enclosures with 1/2" conduit connector. Piston assemblies contain brass SeatScrews in the brass Pistons with filled Teflon™ piston rings, 316 SS expanders. Virgin Teflon™ Seat Discs are held in place by brass DiscScrews. Piston Springs are 302 SS.