KWB Powerbox Drill Set 4, 6, 8 mm Diameter Each 3x (9 Pieces, Metal, Stone and Wooden, BK, Sold as 1 Each, MMM 109154 - - Amazon.com
kwb 4 mm Metal Drill HSS-E 248640 (Industrial Quality, Extreme Heat Resistance, for Difficult-to-Machine Materials, Precision-Ground, DIN 338) - Jobber Drill Bits - Amazon.com
Spiralbohrer, 74-tlg. M35 HSS-CO-Kobaltbohrersatz mit Zylinderschaft, 1,0-8,0 mm, Bohrerwerkzeuge zum Bohren von Edelstahl, Gusseisen, Blech, Stahlplatte, Winkeleisen : Amazon.de: Baumarkt