APC Back UPS 1000 - Back-UPS BX900 R;BX1200 R;DL1000 VNT BR1100 CI;BR1100 CI-RS;BR1100 CI-AS;BR1100 CI-IN BX1300 LCD;BX1500 LCD;BN1250 LCD Battery Replacement; Press Release Tabs and Slide Off Battery Door; Disconnect the Battery Wires; Replace New Battery and Connect Wires