Type: This is a brass swing check valve, designed to prevent backflow in fluid systems.
Manufacturer: Itap S.p.A., an Italian company specializing in valves, fittings, and manifolds for plumbing and heating systems.
Markings: The valve in the image has markings "3" (likely indicating a 3-inch size), "330", and "200WOG" (Working Oxygen Gas pressure rating).
Materials: It features a brass body and plate, with NBR O-rings for the upper and side plugs, and is available with either NBR or metal seats.