Professional 12v booster pack for regular use, designed for starting cars, 4x4s, vans, tractors etc. Powerful 3100A peak, 1700A Cranking. 1 x 30Ah internal battery will jump start up to 150ah batteries. Use and then recharge, the unit charges automatically when attached to the mains and can be left permanently attached to the mains supply while not in use. Made in France.