2-Power 11.1v, 6 cell, 57Wh Laptop Battery - replaces VGP-BPS21

2-POWER's comprehensive range of lithium-ion & polymer battery packs provide unrivalled quality and reliability for virtually all laptop models. Developed using high-grade cells from manufacturers including Samsung and Panasonic; 2-POWER batteries ensure speedy charging, dependable performance, and allow you to go for longer unplugged. 2-POWER's SmartWatch Protect monitors your device during charging and discharging, protecting your device and battery from short circuiting and over-heating.