This check valve has a freely swinging brass disc which makes a metal on metal seal. The sealing surfaces are burnished smooth.
Although these valves prevent bulk backflow, they do not "seal" in the sense of a ball or gate valve. If left standing with liquid under pressure on the back side, the liquid will slowly seep past the valve.
Full flow with minimum pressure loss
Disc is forged brass
Integral hard seat
90 straight pattern
Used to prevent reverse flow in commercial and industrial applications
Threaded ends to ANSI B1.20.1, solder ends to ANSI B16.18