ThinkPad Advanced Ultrabay Battery III 57Y4536

Operates and recharges in the Ultrabay media bay of select ThinkPads, including

• ThinkPad T400, T400s, T500 Series
• ThinkPad R400, R500 Series
• ThinkPad W500 Series,
• ThinkPad T61,T60 Series,
• ThinkPad Z61,Z60 Series
• ThinkPad R61,R60 Series
• ThinkPad X6 UltraBase and ThinkPad X6 Tablet Ultrabase.
• Delivers the power of a second battery, but you do not have to carry around a spare loose battery.
• Offers similar specifications to the standard system battery - Use it in the Ultrabay of the ThinkPad system along with your standard system battery to get up to twice the unplugged usage time as you could get with the standard system battery alone. Since the battery works in the Ultrabay you don't have to suspend the system to swap out the system battery to use the ThinkPad for an extended period of time.