4.5mm cobalt drill bits for hard metal - M35 drill bits by TTP HARD drills
SGS 69235 | 4.2mm Diameter x 6.0mm Shank x 36.0mm LOC x 74.0mm OAL 2 Flute AlTiN Coated Screw Machine Length Drill Bit - All Industrial Tool Supply
uxcell M5 x 0.8 Spiral Flute Tap and 4.2mm Twist Drill Bit Set, Metric Titanium Plated 6542 High Speed Steel Machine Threading Screw Thread Tap Drilling Tool - Amazon.com