This is a 1.5 inch Aluminum Cam and Groove Female Coupler x Female NPT Thread, Type D Quick Disconnect. Cam and groove couplings or quick connect couplings are used as a hose connection to avoid leakages. This kind of coupling is popular because it is considered to be a simple and economical way of re-connecting and disconnecting. Type D couplers are normally used with type A adapters but can be used with Type E and F adapters and DP (Dust Plug) of identical size.
The female side of this adapter will only connect to 1.5 inch male camlock. The female threaded side of this adapter will only connect to a 1.5 inch male National Pipe Tapered (NPT) thread. For example, PVC or metal pipe fitting.
To make a connection, simply slide the adapter into the coupler and with normal hand pressure, press the cam levers down. Uncoupling is as quick and simple as coupling. Just lift the cam arms and remove the adapter.
Maximum operating pressure is 250 psi. Under no circumstances should cam and groove couplings be used for compressed air or steam service!