Marinco Pigtail Adapter 30 Amp Locking to 50 Amp Locking These adapters are equipped with covers and sealing collars (where indicated), and are for use in wet locations. Product Features: Boat Side, female connector attaches to boat inlet or cordset. 50A 125V, Locking w/Sealing Collar System. Dock Side, male plug attaches to dockside receptacle or cordset. 30A 125V, Locking.