350 Ampere continuous rating for inboard gasoline and diesel engines. One-piece tin-plated copper stud design never loosens over time. Terminal studs accept 3/8" or M10 ring terminals. Ignition protected and UL Listed. Selector features make-before-break contact design. Color: Red. (AFD) = Alternator field disconnect. Models; Allow switching while running the engine without damaging the alternator.