Bayonet Socket, Mk.IVA. Stores reference 6D/482. Brass socket as fitted to the Mk.III Tube Adaptor used to enable the use of E-series, G-type and H-type masks in older aircraft fitted with early oxygen systems. These adaptors were also used to connect masks to portable (walkaround) oxygen bottles. The socket has some rubber tube deposits but is in excellent overall condition with clear Air Ministry marks. Stock code O26866A.