12 V Portable Automatic Jump Starter and Power Supply (4000) by Jump N Carry®. A perfect entry-level professional unit, the JNC4000 combines power and ease-of-use in a durable, reliable unit. It features Clore PROFORMER battery technology, specifically designed for vehicle jump starting. With a built-in charger, convenient battery status GA, impact resistant case and 1100 Peak A of starting power, it meets a wide variety of shop needs.