GOOLOO GT4000 4000A Supersafe Jump Starter with 100W Bidirectional Fast Charge & Pre-heating TechGOOLOO GT4000 Jump Starter 4000A Peak Power, 100W Fast Charging, Extreme Cold Ready GOOLOO GT4000 jump starter delivers reliable cold weather performance, capable of starting your car even in extreme temperatures as low as 40F ( 40C). Its advanced battery technology and powerful 4000A peak current ensure instant ignition when you need it most, no matter how harsh the winter conditions get. Never stranded in the cold againthis rugged jump starter works