Double Ended Keychain Screwdriver / bit driver

Saw [AntonFalck's](https://www.thingiverse.com/thing:3160063) design and wanted to add to it by lengthening the holder. I printed off a bunch of his version for Christmas Eve gifts and everyone loved them but wanted the ability to have both a Phillips head and Flat head together.

I really liked the knurling in the original and this gave me a chance to learn how it is done in Fusion 360!

With both bits now available, most screws can be easily opened from your keychain fob.

I had a hard t