10X 0.1-1.0MM/0.3-1.2MM Carbide Micro Mini Drill Bit Tungsten Steel Rotary ToolDescription: This micro twist drill bits set is made of Tungsten steel (drill bit tip) and high speed steel (grip), which is of high strength and high hardness performance. Precise and professional made, the specification of drill bits is range from 0. 1 mm to 1. 0 mm ,0. 3mm to 1. 2mm Application: for all kind of industrial and mechanical purposed use. Parameters: Material: Tungsten steel + High speed steel Specification: about 0. 1 1. 0 mm (0. 1 mm,