Toshiba PMP Gigabeat MES30V battery 3.7v replacement

Toshiba PMP Gigabeat MES30V battery 3.7v.
Replacement Toshiba battery pack to suit Gigabeat MES30V, MES30VW, MES60V, 1UPF383450-830, 1UPF383450-TBF, K33A 3.7v.

Replaces GIGABEAT 3.7V batteries:
1UPF383450-830, 1UPF383450-TBF, K33A.

Fits Following Media Center / MP3 Players
Toshiba Gigabeat
MES30V
MES30VW
MES60V
MES60VK.

Battery Type: Li-ion
Battery Voltage: 3.7V
Battery Capacity: 1000mAh.

The Ah is different on my old battery, can I still use yours?
The Ah (Amp Hour) Rating is the storage (or fuel) of the battery, the higher it is the longer the battery lasts between charges, bit like petrol in your car so a higher or lower one makes no different to the performance, just the length of time you can use the battery for between charges.

Length = 53.18mm
Width = 34.23mm
Height =4.26mm.