The XL 12v Pro Robopak® is very powerful - 33 amp/hr @ 12v - and incorporates state-of-the-art battery warning and shut down circuitry. It is designed to protect valuable instruments and equipment from damaging low voltage conditions and will extend the life of the Robopak® by preventing over-discharge. By monitoring the Robopak’s voltage at all times, the unit senses if it has been drained to a predetermined set cutoff voltage. Prior to (60 seconds before) reaching the disconnect voltage, an audible alarm (beeper) will sound and the super bright LED will flash. At that point, the user is warned that they have 60 seconds until the Robopak® will shut down - low voltage disconnects. The 12v Pro Robopak® can be provided with any or all of the warning devices prior to shutdown. A user may want the audible alarm only, the flashing light only, or as provided by the "Deluxe" model, the flashing light and audible alarm. All combinations are available.  The 12v Pro is encased in a heavy-duty all weather plastic casing and it contains dual power receptacles - Marine grade 12v receptacle and 3 prong twist lock port for powering items. The 12v Pro requires AC Charger Cat. No. 4346.