VZSU71 is 10.8v and 69Wh 6750 mah
VZSU65 is 11.1v and 56Wh 5.2Ah
VZSU29 is 11.1v and 6.6Ah 6600mah
VZSU46 is 10.65v and 8.55Ah
VZSU72 is 4500mah
Lightweight Battery for the Panasonic Toughbook 31 MK2 and Panasonic Toughbook 53 MK1, Genuine Panasonic Toughbook Replacement Battery
The CF-VZSU72U is the replacement Panasonic Toughbook Battery for Part Number CF-VZSU72
The CF-VZSU72U is the original battery that comes with the Toughbook 31 MK2 i3 only and the Toughbook 53 MK1 i3 only, the i5 Toughbook 53 and Toughbook 31 come with a 9-Cell battery and will not work with this battery.
Long Life Battery for Toughbook 52 MK4 and Toughbook 53 MK1, Genuine Panasonic Toughbook Replacement Battery for Toughbook 52 and Toughbook 53. The CF-VZSU71U replaces the Panasonic Toughbook Battery part number CF-VZSU71.
The CF-VZSU71U is the genuine Panasonic battery that comes with the Toughbook 53 and Toughbook 52, it didn't come with the i3 and p8600 of the 52, or the Toughbook 53 i3 but this battery will work with those laptops and increase the battery life compared to the original battery that came with them.
Lightweight Battery for the Panasonic Toughbook 52 P8400 MK2, Toughbook 52 i3 MK3 and Toughbook 31 i3 MK1 and MK2, Genuine Panasonic Toughbook Replacement Battery.
The CF-VZSU65AU is a lightweight (6-cell) battery, it comes standard on the Toughbook 52 P8400, Toughbook 52 i3 and the Toughbook 31 i3, the Toughbook 52 P8600, Toughbook 52 i5 and Toughbook 31 i5 Toughbook Laptops came with the 9-cell battery, this battery will not work on the i5 or P8600 Toughbooks. The CF-VZSU65AU replaces the following Toughbook Battery part numbers CF-VZSU65, CF-VZSU65U.
Long Life Battery for Panasonic Toughbook 30 MK3 (CF-30K) and Panasonic Toughbook 31 MK1 and MK2, Genuine Panasonic Toughbook Replacement Battery.
The CF-VZSU46AU replaces the following Panasonic Toughbook Battery part numbers. CF-VZSU46, CF-VZSU46U,
The CF-VZSU46AU is the original battery that came with the Toughbook 30 and Toughbook 31 (i5 units, the i3 came with the 6-cell battery, this battery will increase the capacity of the Toughbook 31 i3 models)
Long Life Battery for Toughbook 29, Toughbook 51, Toughbook 52 MK1, Toughbook 52 MK2 and Toughbook 52 MK3. Genuine Panasonic Toughbook Replacement Battery
The CF-VZSU29ASU is the replacement Toughbook battery for the compatible laptops listed above. With the Toughbook 52, the CF-VZSU29ASU is the same battery that came with the High End version of the laptop (a 9 Cell Battery), the low end version of the Toughbook 52 comes with a 6 Cell and this battery can be used as an extended life battery for the low end 52 as well.
The CF-VZSU29ASU replaces the Toughbook battery models: CF-VZSU29, CF-VZSU29AU, CF-VZSU29A
Life will beat you into submission.