Battery Case for Hearing Aid Batteries (Type 13)

I have a friend who uses hearing aids for both ears. 

That is why he always keeps some batteries with him. The package is thin cartboard and plastic and when carried in the pocket they can fall out.

The batteries gets activated when the brown flip gets pulled off, so it is important that they stay on there until needed. They still have a minimum of Voltage and if they touch like when they fall out in the pocket they looses what they have and won't work.

So I made him this. It fits 8 Batteries and fits nicely in the pocket. Only the middle turns, buttom and lid are fixed together.

I Made this for the Type 13.

On the blank part of the middle part I wrote his name, but I left it out for the shared on.

Feel free to use and share it - I only have one request, If you print it for someone who need it, don't let them pay for it.

I used an M3 sink-head 10mm screw to put it together. The is room for a small spring and 2,5mm ball, and detents in the lid if you want it to snap.

Print instructions

I Used 0,15mm layers, 4 perimeters (only 2 should be needed), infil around 15-40% what you like. I only used supports in the middle of the lid.
And the Hilbert Curve on top looks nice!