Benefit: Cutting edges strictly avoid partial hole, ensure quality, sharp and twisted flute will make drilling easier and suitable for wood, aluminum, plastic, etc. Material: Made of quality material, durable and easy to use. Usage: suitable for PCB drilling machine, engraving machine and special high precision drilling equipment. Sharp design: ideal for drilling via printed circuit boards. Occasions: Drills are ideal for delicate drilling through hard materials for model engineering, jewelry repairs, crafts, archeology and science lab work. Feature: Usage: Suitable for PCB drilling machines, engraving machine and special high precision drilling equipments. Benefit: Cutting edges strictly avoid partial hole, ensure quality, sharp and twisted flute will make drilling easier, suitable for wood, aluminum, plastic, etc. Pointed design: ideal for the drilling via printed circuit boards. Material: Made of quality material, durable and easy to use. Occasions: Drills are ideal for delicate drilling through hard materials for model engineering, jewelry repairs, crafts, archeology, and science lab work. : Main Material: Tungsten Size: about 2.1-3.0mm Color: Positioning ring color is random Note: 1.1inch=2.45cm/1cm?0.393inch 2.Please allow 1-3cm error due to the manual measurement. Pls make sure you don''t mind before you bid. 3.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thanks Package including 1set mini engraving drill bit