Your APC BACK-UPS ES BE350G unit requires 1 replacement UPS battery 12V 3.4AH. The APC BACK-UPS ES BE350G replacement battery has high performance, high discharge design, wide operating temperature range, and long expected service life. The replacement battery meets or exceeds the original manufacturer specifications and ensures your satisfaction regarding quality, durability, and performance. You have to install the new APC BACK-UPS ES BE350G replacement battery in the UPS unit in the same original configuration and reuse the existing cables and hardware. Please check your existing battery for dimensions prior to ordering as manufacturers may change requirements without notice. We supply only fresh date code products that carry industry leading two year warranty.