These can be used to repair damaged internal threads (tap) or external threads (die) or to cut totally new threads into a fresh drill hole or onto a plain rod of the correct material.

Gunpla Tap and Die Set 20 Pieces Tungsten Alloy Steel Metric Tap and Die Kit M3-M12 Combination for Cutting External and Internal Thread with Storage Case
4.0

Hi-Spec 39pc Imperial SAE & Metric Tap & Die Set. Complete M3 to M12 / #4 to 1/2in tap Spanner Set. Tapping and Threading Tools with Tap Wrench & Screw Pitch...
4.0

Gunpla 32 Pieces Tap and Dies Set Tungsten Heavy Duty Alloy Steel Metric Screw Threads Cutting Tools Taper Drill Threading Kit with Storage Case
4.0