Sony PCG-FXA59 - Manual (Page 23)

To insert a second battery pack
1. If another device is in the multipurpose bay, remove that device.
2. Insert the battery pack into the multipurpose bay.
If the battery is being used, the battery 2 indicator turns on.
Second battery in multipurpose bay
3. Attach the weight saver to the notebook to stabilize the battery pack. See Using the Weight Saver for more
information.
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