This adapter will refill CO2 for Benjamin Discovery & Marauder and Crosman Challenger. It has a C GA-320 fitting with .825x1/4 thread,8 in stainless steel hose, female Foster fitting. It can also be used with CO2 paintball tanks. Do Not Use for filling gun with pressurized air. SPECIFICATIONS:Type :Air RifleAction :CO2Caliber :Airguns & PaintballCapacity :UnlimitedFinish :Silver