Duralast 800 Peak Amp Jump Starter GL055B is a portable advanced lithium-ion battery jump starter. It is strong enough to deliver up to 800 peak amps of jump starting power up to 25 times on a single charge. It also functions as a portable power pack with a 2.4-amp USB port to charge smartphones and mobile devices up to four times faster than conventional USB chargers. An ultra-bright built-in LED light including a steady glow, emergency flash for an SOS signal, and a strobe mode. Other features include a smart clamps with reverse polarity, short circuit, high temperature and reverse charging protection.