Marinco Pigtail Adapter, 50 Amp Locking to 50 Amp Locking Pigtail adapters are equipped with covers and sealing collars where indicated, and are for use in wet locations. Marincos unique sealing collar system with cover joins the adapter to the cordset with a positive, mechanical connection. Product Features Boat Side Female connector attaches to boat inlet or cordset, 50A 125V, Locking wSealing Collar System. Dock Side Male plug attaches to dockside receptacle or cordset, 50A 125250V, Locking.