About this 3D model

These holders are designed for metric drill sets, and have a space for 1 to 10mm bits at 0.5mm spacing, 11, 12, 13, and the tap drills 3.2, 3.3, 4.2 & 4.8. Holes were a fraction tight on mine. I'm not going to redesign it. Just bore them out with the suitable drill bit.