Features Cast iron check valves have good sealing performance and reliable performance. The single-acting cast iron check valve with piston is made of high quality metal for a long service life. Cast iron check valve with piston in one direction, suitable for air compressors etc. The cast iron 3 way check valve is easy to install, the product has low resistance. Contact us at any time if you have any problems and we will reply you within 24 hours. We guarantee you will get the best solution and service. Specification: Item type: check valve. Material: Iron Interface Size: 1/2" x 1/2" Thread hole: approx. 21x21x10mm/0.8x0.8x0.3in Compatible: for air compressors etc. Package list: 1 x check valve. Package List 1 x Check Valve