I use this to hold my M3, M4, M5, M6, M8, and M10 Taps. I also used two M6x12 to hold two little arms in place that can swing in order to keep the taps inside the case. I used a 5mm rod/dowel to use as a hinge. These taps use a standard ¼ hex shaft.
The Taps I used: https://www.amazon.com/gp/product/B088R8T4YJ/ref=ppx_yo_dt_b_asin_title_o03_s01?ie=UTF8&psc=1
The Screws that I have/used: https://www.amazon.com/gp/product/B09WK58Q9Q/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1
The author marked this model as their own original creation.