Dixon ADA4030EZ Aluminum EZ Boss-Lock Cam and Groove Reducing Hose Fitting, 4" Socket x 3" Plug Cam and groove fitting with handles that remain locked when engaged to help prevent disconnects One female cam coupler end for connecting to male groove adapters and one male groove adapter end for connecting to female cam couplers Aluminum for resisting corrosion and tarnishing Corrosive-resistant investment cast stainless steel cam lock levers for locking the fitting's male groove adapter into female cam couplers Nitrile butadiene rubber seal rated for petroleum service, ethanol to E100, and biodiesel to B20