Lenovo ThinkPad T61 Hardware Maintenance Manual page 53

Table 6. Specifications (continued)
Feature
Battery
AC adapter
Preinstalled operating
system
Description
v Li-ion battery (4 cells) 2.6 Ah
v Li-ion battery (6 cells) 5.2 Ah
v Ultrabay Slim Li Polymer battery (3 cells) (for T61)
v 65-watt type
v 90-watt type
v Windows XP Professional
™
v Windows Vista Home Basic
v Windows Vista Home Premium (32 bit)
v Windows Vista Home Premium (64 bit)
v Windows Vista Business (32 bit)
v Windows Vista Business (64 bit)
v Windows Vista Ultimate (32 bit)
ThinkPad T61, R61, and R61i (14.1-inch widescreen)
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