Abstract: A vent plate for mounting in a termination receptacle for an air supply duct has an upper plate portion integrally molded with a sleeve portion having a hollow interior for receiving air from the termination receptacle and communicating with a central hole of the plate portion. The plate portion has a peripheral flange portion projecting outwardly from and surrounding the central area including a down turned edge flange so as to terminate at an outer sharp edge which is spaced axially from the plane of the front face. A separate center plate with a series of holes so as allow the air to escape is shaped and arranged to be received in the central opening and is held in place by peripheral ribs and sits against supporting abutments in the sleeve.

Abstract: A high pressure air supply duct is terminated by a termination receptacle defining a cylindrical housing with an inlet pipe connected to the duct and generally at right angles to the axis. The housing has one end closed and a mounting flange member at the open end for attachment of the housing to a mounting surface. A generally cylindrical damper sleeve has an open discharge end connected to a vent plate and an insertion portion extending to the bottom of the housing for receiving the air therefrom. The vent plate has a plate portion with a central perforated discharge area which is perforated for the passage of air therethrough and a peripheral surrounding flange and can be rotated about the axis of the housing to rotate the damper sleeve. The damper sleeve has a projecting notch engaging into a slot in the housing to hold it in place.