Replacement Ni-MH Battery for RADIO SHACK ET598 - 3.6V, 600mAh. Restore power to your compatible Radio Shack device with this brand new Nickel Metal Hydride battery. Engineered to meet original specifications, this battery provides reliable 2.16Wh power in a compact size (42.64 x 30.00 x 14.45mm). Perfect for models like the ET598 and other compatible Radio Shack cordless products.