Up for sale is a used 90-degree Air Line Compression Fitting / Adapter.
It was pulled from a Peterbilt semi truck.

Side A: 1/8" NPT female (1/8"-27 NPT)
Side B: 1/8" O.D. (3.16mm) Plastic Hose / Pipe
Material: Brass

This adapter is commonly used on semi trucks to connect the plastic air pressure lines to valves, gauges, etc.

Please see photos.
Questions welcome. Thanks for looking.