For use with the Breg Kodiak Cold Therapy Unit. Each battery pack comes with four replaceable AA batteries ready to power 10-14 hours of motorized cold therapy. Simply slide the battery pack on top of the Kodiak unit. Provides up to several hours of use between charges. Offering the only battery powered option on the market, Breg ensures your patients can enjoy the benefits of cold therapy from anywhere: on the sidelines or in the backyard.