NAPA inverters are built to give you the maximum power for all your charging needs in your car, truck, RV or boat. Built to supply you with clean household AC power and supply 115V power for all your devices including cell phones, laptops, Mp3 players and more. Providing maximum charging power in the shortest time, all USB's are 2.4 amp and wired separately so all ports have 2.4 amps of charging power available at all times, no matter how many devices are plugged in.