Features : Heavy duty aluminum alloy construction, center of gravity at handle, easy to operate. Push to couple, pull to release. Unique locking action that insure positive connection and uniform seal compression. 360° round sight glass window on top. 5 ° angled four bolt flange pattern with variety of different inlets to meet any requirement. Tetrafluorethylene Resin by DuPont viton & teflon are registered names.