Battery holder for vintage Texas Instruments calculators TI58 and TI59

To make the electrical contact between the different battery slots, it's necessary to insert 2 paper clips at height 11.2 mm. This pause is included in the 3mf file. 

Holes in the body allow to test the electrical voltage path along the 3 batteries.

The 2 flat metal contacts are unmounted from the original BP-1A pack to be re-used in the new pack.

To improve the contact with the battery and the paper clip, insert additional aluminium foil in between.

Starting from the model proposed by XDUR, I extended it to receive 3 rechargeable batteries. The final set exactly fits in place of the original BP-1A module.