Free for shipping (about $20, it's heavy). It's 10 years old. An Avaya PW9125 2000 20R. This one is 2U rack size, but ours has the pedestal foot option.
2000 VA, 1400 watts it used to back up our PBX but now we have a unified building-wide inverter. It's been through 2 sets of batteries in 10 years. I removed the second set since they are dead. The front bezel is cracked at the top, the battery case is still inside with the wires to jumper 4 SLAs if you want to use it for it's original purpose. It takes 4 12v 9AH SLA's
New, they are $400, and it puts out a sine wave. http://microxusa.com/cgi-bin/page_main.cgi?UPS&1&05146001-4106&&&&&118908&&&
There are connections in the back for external batteries for extended run time.