Mindlab dls

I have a mindlab dls mental fitness system for about 10 years.(similar ao mind's eye).
I need to replace the rechargeable battery.
The battery in the unit is nt 70 aak.
What can i change battery?
I live in brazil.

Are you good with electronics?
If so, take out the batteries and take them to a battery store and try and match them up.

The MindLab was manufactured in the early 1990's, and the fact that yours is still working is pretty impressive.
MindPlace/Synetics products over the years

I had a mindlab dls, I loved it but sold it a few years ago, i should have kept it for part of my collection. I had a mastermind too, that was my first light and sound machine back when the company was synetic systems.