HQRP Battery for SportDOG SportHunter SAC00-12544 1225 SD-1225 1825 SD-1825 SR-300 SR300 Dog Training Receiver Collar Sport-Hunter Sport-Dog + Coaster HQRP&reg; Rechargeable Collar Battery Replacement plus HQRP&reg; Coaster; Battery Voltage: 7.4V; Capacity: 200 mAh; Li-Pol; Dimension: 27x41x6mm; 200 Days warranty!