Check Valve, In Line, Inlet (In.) 1/4 in FPT, Outlet (In.) 1/4 in M(NPT), Brass, Max. Pressure (PSI) 250 psi, Cracking Pressure (PSI) 0.1 psi, Hex Size (In.) 11/16 in, Flow Range Free Air (CFM) 1 to 9 cfm, Max. Temp. (F) 250 Degrees F, Horizontal, Vertical Mounting, Length (In.) 1 9/16 in, Stainless Steel Spring Material, Stainless Steel Poppet, Tank Check Valve for Small Compressors or as Components in Pneumatic Circuits WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov - Nickel (Metallic)