Retaining Head, Compatible with Brand Bernard, Tough Gun, Series TOUGH LOCK(TM), Gas Diffuser Number 404-20, Compatible with Series TOUGH LOCK, Compatible with Model Magnum(R) 300, Magnum(R) 400, Spray Master(TM) 350, Spray Master(TM) 450, Tweco #3, Tweco #4, WeldSkill(R) 400, Connection Type Slip-On, Duty Rating Heavy Duty, Welding Processes MIG Welding (GMAW), Connection Thread Size 9/16 In.-18, Connection Thread Type Slip-On. This item has been restricted from sale in the following state(s): []