1/4" NPT X 3/8" Hose barb
This is an elbow fitting.
Size is based on the vacuum hose.
Our hoses typically have the size on them.
System models 1040/1060 exhaust hose fitting. (systems 2020 and newer, white unit)
Blue tank systems barb fitting for vacuum pump to connect the vacuum hose. (some systems older than 2020)