I don't know how many here are aware that Clippard makes a multitude of small pneumatic products that might come in handy for flow bench use.
I used some of their fittings hose and switches when I set up my dyno.
Here is their web site;
I'm going to be their toggle switches for the bi-directional pitots, just flip a switch to change the pitot impact FP1 source for exhaust or intake testing.