VINTRONS BP-HP550-11 Cordless Phone Battery 2.4 Volt, Ni-MH 700mAh - Replacement For SONY MDR-RF810/840/850/860/925/970/4000 Capacity: 700mAh / 1.68Wh Type: Ni-MH Volts: 2.4V Size : 46.00 x 23.00 x 11.00mm Certificated with ISO9001, RoHS & CE;