30 Grobet Twist Drill Bits Great for Metalsmiths, Metal Working & DrillingThis is a new set of 30 Grobet twist drill bits. Great for drilling metal, plastic, wood and stone. Each package has a set of six drill bits. Made in Switzerland with Swiss quality and workmanship. All drill bits have 3/32" (2.3 mm) shanks.You receive 6 Drill bits size 4/0 with an ISO of 006 and measure approximately 0.60 mm in diameter 6 Drill bits size 3/0 with an ISO of 007 and measure approximately 0.70 mm in diameter 6 Drill bits size 2/0 with an ISO of 008 and measure approximately 0.80 mm in diameter 6 Drill bits size 0 with an ISO of 009 and measure approximately 0.90 mm in diameter 6 Drill bits size 1 with an ISO of 010 mm and measure approximately 1 mm in diameter.