The SMC AW-D series of modular filters are filter regulator units for the AW40A-D series of FRLs. It has G type pipe threads and the port size is 1/2 inch. It comes with normally open float type auto drain and it comes without backflow function. This model has square embedded type pressure gauge (with limit indicator).

Integrated filters for space saving and requires less piping
Models with the backflow function include a mechanism which allows for the air pressure in the outlet side to be released to the inlet side