Marinco on-board charger inlets, make battery charging through an on-board battery charger, safer and more convenient. Inlets mount on the boat exterior and are hard-wired directly to the charger. To use, just open the flip lid cover, and plug an extension cord into the inlet. All hatches remain closed and locked throughout the charging cycle for added security. Isn&';t that easy? 1-7/8" diameter drill hole Mounts easily to fiberglass and aluminum hulls Perma-Lock terminals and color coded wire entrance holes, make wiring a snap UV resistant housing/cap Low profile cap won&';t catch fishing line 15 amp rating, 125 Volts, NEMA Configuration 5-15P Nylon, Vinyl housing, and nickle-plated brass blades Perma-Lock(TM) design Mounting: Either front mount by three #6 x 5/8 screws (provided) or rear mount by 1A 1/2" conduit locknut (provided)