R1/4" (BSPT) male quick coupling for 6 mm (1/4") air hose is made of steel and coated with a corrosion-resistant coating. Opening 7.4 mm. max air flow 2200 l/min@6bar. Manufacturer PCL. England.
R 1/4 (BSPT) - British Standard Pipe Taper (conical thread). angle between threads 55°.