I have this information third hand so it might not be still available.

TGA Electric leisuire power pack This is a power pack to add on to a wheelchair. This item is 8+ years old and is free to a good home or donation to the MND Association. Please note, there is no charger or control, it is just the battery pack available. The location for collection is Taunton.

I think that it is a complete system that helps you push a manual wheelchair.

If interested please post below.

Love Terry