Worx 254 bit cylinder
Didn't like the models I saw, so I designed my own
no supports
no glue (if your printer is tuned well enough, the layer lines will grip well enough)
8x8mm cylindrical magnet
1/2 of a ballpoint pen spring
I inherited about 50 of these bits from other projects, printing these for standardization and organization
obviously print bottom pin upside down and top pin flat side down