Roxon Flex 4mm hex holder, pin, and tweezers
This tool holds 3x 4mm hex bits, a pin or needle, and the original Roxon tweezers. It takes up 2 tool slots. If combined with a 1/4" to 4mm bit adapter in the screwdriver insert, then 4No 4mm bits can be carried together. There is a recess at the base of each 4mm hex slot for a 3x1mm magnet.
I found I had to grind down the length of some of my 4mm bits to fit.
Only tested on a Flex Companion.
Re-mixed from this tool blank: https://www.thingiverse.com/thing:6565570/remixes