Applications: Small Air Compressors with High Flow Requirements, Set Pressure Tolerances: ± 3% of Set Pressure, Temperature Range: -65°F to 400°F, Construction: Seat Cap and Piston C360 Brass (ASTM B-16), 17-7 Stainless Steel Spring and Silicone Seal, Bubble Tight to Within 5 psig for Set pressure 50 psig or Less, Bubble Tight to Within 10% for Set Pressures Greater than 50 psig. 100% Testing or 2.5 AQL Sample Testing, Conforming to AP1 527, Stamped with the UV and NB Symbols, Ever seal 483 Sealant Standard.