High Quality high capacity rechargeable battery. No memory effect. Can be charged or discharged as needed without loss of capacity. Overcharge protection with built-in battery life microchip. Volts: 3.7V Battery Type: Li-ion Capacity: 2500mAh Dimension: 77.20 x 54.00 x 6.20mm Compatible Part nos: 2500031 2500060 W-5 Compatible Models: Sprint AirCard 770S AirCard 771S Mobile WiFi Hotspot. † SMAVCO and the SMAVCO logo are trademarks of SMAVCO LLC.