This is a brand new replacement battery cartridge #3 (RBC 3, RBC3) for several APC UPS Smart-UPS and Back-UPS models (Back UPS 450, Back UPS 520, Back UPS 575, Back UPS 600, Back UPS 600C). ExcessUPS offers only the highest professional grade replacement battery cartridges that are always fresh stock, never used and definitely not refurbished. These RBC3 batteries are designed to handle maximum APC UPS loads with ease, ensuring a generous runtime, long life and guaranteed total protection against power anomalies such as blackouts, brownouts, spikes, sags and surges. This RBC3 APC UPS battery pack consists of two 6V, 12Ah batteries. All of our APC RBC 3 replacement batteries include all of the necessary connectors and fuses to ensure a safe and easy, plug & play installation. We stand behind the quality of our APC RBC batteries so strongly; we use them in all of our refurbished APC UPS battery back up units. All of our APC UPS RBC batteries include our ExcessUPS 1-Year Complete Coverage Warranty!