Occasionally you want to field test an idea for an electronics project that requires a specific voltage or you want to see what real world recharging and depletion are like. 

I designed this pack to use standard zinc/nickel strips so that you can quickly set it up for series or parallel using one to three 16340 batteries. The zinc strips are easy to insert and run securely across the battery “springs”—a quick note on those, occasionally one of them snaps but it doesn't seem to affect the functionality in any way—and can be fed neatly along a rear channel when setting batteries up in series so that your positive and negative are on the same side of the case.

There are very small holes on each corner to make it easy to insert breadboard pins if you are testing your project that way.

This prints quickly (30 to 40 minutes, depending on your printer) without supports.