Deep Blue Professional hurricane category 5 professional AC/DC battery operated pump automatically switches to battery backup in the event of power failure and recharges when power is restored. The integrated d-cell battery slots of the pump are for use when main battery pack is exhausted. The pump is adjustable and comes with electronic flow control with interval battery extension technology. Adjustable flow control with interval battery extension technology. This pump also has two output modes, with the full mode to pump continuously for 14 hours on full battery and an interval mode that runs one minute on, one minute off extending battery operation up to 28 hours. Removable, 6-volt nickel cadmium battery pack included. Designed with dual output ports and impact resistant housing. Continuous operation with or without power.