This is an AC Regenerator (like the PS Audio Power Plant). It also has internal batteries (UNlike the PS Audio Power Plant). It has an option for added external batteries. It is in excellent working and cosmetic condition.
This model has a capacity of 1050 watts. The internal batteries last 7 minutes at full power and 18 minutes at half power (575 watts). It has been cleaned internally (see pictures), unlike the "refurbished" models I've seen.
This commercial/industrial unit has also been modified for home audio use by switching the rear fan to a Nexus (see picture), which is famous for being quiet. The stock fan was so noisy it could be heard more than 50 feet away, which I found impossible to live with.
While a picture displays the current batteries as "100% charged", this must be disregarded as these batteries are now old and can no longer handle a load.
There are THREE of these 9120 1500 models for sale, all in the same condition. While I've had no problems with any of the models, with the exception of routine battery replacement, they are still being sold "AS-IS".
The price is $ 250 EACH, with NO batteries, which will also be safer to ship and reduce the total cost (almost $ 20 NET).
Battery Replacement Website: http://www.atbatt.com/eaton-powerware-9120-1500-batteries.asp
PayPal, add 3.5%.