Drills (all measurements in inch) Tungsten vanadium twist drills Purpose-made, selected tungsten vanadium steel with high concentricity. Manufactured from a one-piece blank. High hardness for optimum life expectancy. For drilling metal, non-ferrous metal, plastic, circuit boards and wood. Work speeds: hard materials approx. 3,000 rpm, soft materials approx. 8,000 rpm. All shanks 3/32" (2,35 mm).