21PCS Straight Shank Twist Drill Bit Material:high speed steel. Standard:DIN338. Production technology:fully ground. Surface treatment(color):bright Specification:1/16"~3/8" by 1/64". Packing details:plastic case with double blister. Drill for metals,wood&some plastics. We can manufacture drills from DIA.0.3mm to DIA.13mm,according to customer's requirement.