Specifications: Carbide twist drill bit is sharp, and it has fast drilling speed. It is very helpful for your drilling work.Wear-resistant twist drill bit features sharp, it has fast drilling speed. And it is very helpful for your drilling work.High precision twist drill bit is very helpful for your drilling work. It is sharp and has fast drilling speed.Features: Featured with triangular shank, the twist drill bit is non-slip, safer to use. And it adopts threaded single groove design, which brings fast chip removal.It is the triangular shank design that makes the twist drill bit non-slip, safer to use. And it adopts threaded single groove design, which brings fast chip removal.It is suitable for drilling ceramics, aluminum iron, marble, cement board, wood, plastic, etc.6mm Size: 10cm x 0.6cm x 0.4cm/3.94" x 0.24" x 0.16", Length: 100mm/3.94", Shank Diameter: 4mm/0.16" (Approx.)8mm Size: 11cm x 0.8cm x 0.6cm/4.33" x 0.31" x 0.24", Length: 110mm/4.33", Shank Diameter: 6mm/0.24" (Approx.)10mm Size: 12.1cm x 1cm x 0.8cm/4.76" x 0.39" x 0.31", Length: 121mm/4.76", Shank Diameter: 8mm/0.31" (Approx.)12mm Size: 12.2cm x 1.2cm x 0.7cm/4.8" x 0.47" x 0.28", Length: 122mm/4.8", Shank Diameter: 7mm/0.28"(Approx.)notes: When drilling with high hardness materials, please add water to cool down to avoid burnout of the drill. Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.