The RBC35 Replacement Battery Cartridge that we sell is made of high quality long life batteries. This battery is not OEM branded, but is designed to meet or exceed OEM battery without the high price from the manufacturer. These batteries are designed to handle UPS loads and are tried and tested to meet and exceed manufacturer's specifications. The batteries that we sell are the same high quality batteries we install into the UPS systems we offer. By purchasing high quality batteries you are ensuring that your UPS will perform as required during a power outage. Having high quality batteries is having peace of mind knowing that your equipment is protected. The RBC35 battery pack that we sell is ready to go, plug and play installation. Pull out the old RBC35 and replace it with this new RBC35 and you're ready to go.