This is a simple screwdriver handle with bit storage. I wanted a screwdriver that was 1" in diameter to fit in my belt holster that also had bit storage, i couldn't find one, so I designed one using tinkercad and made it. The end cap is free spinning. There are two tabs that have to be lined up with two slots in the handle. you press it in until it stops, twist it 90 degrees until it lines up with two more slots and press it in the rest of the way. it will then freely spin. To remove the cap, pull gently while spinning to line it up with the slots, once it pops out to the first stop, twist it 90 degrees and pull it out the rest of the way. This system works well and is quite durable. however if you hand it to someone that doesn't understand how it works, they will break the cap by being a forceful brute. I suggest printing a spare cap if you intend to let morons use it.

You will need a bit holder that you can pick up from your local hardware store. there is a retention nub on the inside of the hex shaft to keep the bit holder in place.

Since this is a tool, i suggest 100% infill.