Smith H753 Flashback Arrestors. These will go between the regulator and hose. (Regulator Mount). Designed to help prevent accidents caused by reverse gas flow or flashbacks. Built-in check valve protects against reverse flow. Brass construction for long life. 100% tested for reliability and performance. Color coded by gas service for easy identification. Made in USA. Capacity: Welding: 3/8″ / Cutting: 12″. Maximum inlet pressure: Acetylene: 15 PSIG / Other Fuel gases: 22 PSIG / Oxygen: 145 PSIG. Hose size: 9/16″ – 18 std. B connectors. Package of 1