Description: Designed with a triangular shank to make the drill clamping tighter and less likely to slip, it ensures safe operation and improved work efficiency. Fast chip removal is made possible by the dual-spiral flute design, which makes the drilling quick and smooth. Made of hard alloy material, the triangle drill bit is durable and has high hardness. The storage box is 15.8cm long, 6.7cm wide and 1.4cm high. Triangular drill bits can easily drill various materials, such as ceramic, tile, marble, concrete, glass, metal, etc. Item Name: Drill Bits Material: Hard Alloy Color: Orange Shank Type: Triangular Shank Specifications: 5mm, 6mm, 8mm, 10mm, 12mm Features: Anti-Slip Design, Fast Chip Removal, Wear-Resistant Size Details: 5mm: Total Length: 82mm/3.23", Drill Bit Diameter: 5mm/0.2", Working Length: 43mm/1.69", Shank Diameter: 4.5mm/0.18" (Approx.) 6mm: Total Length: 100mm/3.94", Drill Bit Diameter: 6mm/0.24", Working Length: 56mm/2.2", Shank Diameter: 7mm/0.28" (Approx.) 8mm: Total Length: 116mm/4.57", Drill Bit Diameter: 8mm/0.31", Working Length: 70mm/2.76", Shank Diameter: 7mm/0.28" (Approx.) 10mm: Total Length: 120mm/4.72", Drill Bit Diameter: 10mm/0.39", Working Length: 73mm/2.87", Shank Diameter: 8mm/0.31" (Approx.) 12mm: Total Length: 120mm/4.72", Drill Bit Diameter: 12mm/0.47", Working Length: 73mm/2.87", Shank Diameter: 10mm/0.39" (Approx.) Storage Box Size: 15.8cm x 6.7cm x 1.4cm/6.22" x 2.64" x 0.55" (Approx.) Notes: 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. Package Includes: Style 1: 5 x Drill Bits (1x 5mm, 1x6mm, 1x8mm, 1x10mm, 1x12mm) Style 2: 5 x Drill Bits (2x6mm, 1x8mm, 1x10mm, 1x12mm) Style 3: 6 x Drill Bits (1x5mm, 2x6mm, 1x8mm, 1x10mm, 1x12mm) Style 4: 7 x Drill Bits (2x5mm, 2x6mm, 1x8mm, 1x10mm, 1x12mm) Style 5: 7 x Drill Bits (4x6mm, 1x8mm, 1x10mm, 1x12mm) Style 6: 6 x Drill Bits (2x6mm, 2x8mm, 1x10mm, 1x12mm)