Modern rotating screwdriver set 4.2mm and 6.4mm

Here is a screwdriver set with a modern and convenient design. I wasn’t completely satisfied with the ones available, so I decided to create my own. The lower part of the screwdriver rotates freely.

I recommend printing the included "calibration" files first to achieve the optimal fit for the tips. Use a measuring tool, as shown in the image, to precisely determine the correct tightness. 
 

Printing these requires supports, as you can see in the image. File already include this and other necessary settings, but make sure to check it yourself! Small magnets can also be used. 

Print with the strongest filament you have. I recommend PA-CF. Tough PLA might work well too.