With the STANLEY SS4LS portable jump starter and power pack, you no longer need to dread roadside emergencies when your vehicle won’t start. This ultra-compact, portable device delivers serious power and provides up to 20 jump starts or recharges up to 10 electronic devices off a single charge; holds a charge for up to a year without needing to be plugged in. That’s enough power to jump-start most vehicles including V6 powered cars and trucks; all without the need to use another vehicle for assistance. Simply connect the clamps to the battery, turn on the switch and start your vehicle. The reverse polarity alarm will alert you when there is an improper connection. A bright LED light helps you work in the dark. The built-in dual 3.1 amp USB port comes in handy to charge your phone and electronic devices on the go or during an unexpected emergency power outage. The STANLEY SS4LS portable jump starter and power pack includes both AC and DC adapters allowing you to recharge from practically anywhere and a limited 1 year manufacturer warranty.