Product overview 1 pack of 4.9 mm drill bits (diameter 4.9 mm) with an overall length of 86 mm (3.39') and a flute length of 40 mm (1.57'). 135° splitpoint tip to reduce walking and start holes precisely in metal, wood, and plastic. Key features and benefits Precise starts and cleaner holes: 135° splitpoint geometry reduces tip walk and improves centering so you can drill accurately without pilot holes in many materials. Long life and durability: Made from M42 cobalt speed steel with 8% cobalt for hardness, heat resistance, and crack resistance—designed to handle strength and difficulttomachine metals. Improved surface protection: Titanium nitride (TiN) coating increases wear and corrosion resistance, extending tool life and maintaining cutting performance longer. speed performance: Cutting edges retain sharpness at RPM, making the bits suitable for fast, precise drilling. Costeffective: M42 cobalt construction delivers about 35 times longer tool life compared to standard HSS, lowering cost per hole for production or repeated DIY tasks. Reliable in production: Balanced wear resistance and toughness make these bits suitable for automated equipment and volume machining environments. Specifications Diameter: 4.9 mm Overall length: 86 mm (3.39') Flute length: 40 mm (1.57') Tip angle: 135° splitpoint Material: M42 cobalt speed steel (8% cobalt) Coating: Titanium nitride (TiN) Compatible materials and typical uses Metals: strength steels, stainless steel, and other difficulttomachine alloys where heat and wear resistance are required. Wood and composites: Dense hardwoods (rosewood, teak), hardwood sheets, composite boards, and thin wood panels for joinery and fine work. Plastics: Clean, accurate holes in a variety of plastic materials. Practical use scenarios Furniture making and joinery: Drill precise mortiseandtenon starter holes and dowel holes in hardwoods like teak and rosewood without frequent bit changes. Metal fabrication and : Produce accurate holes in stainless or strength steel parts where heat buildup and tool wear are concerns. Detailed carving and craft work: Create small, clean holes in thin wood sheets and carved components where clean starts and minimal splintering are critical. What makes these drill bits stand out M42 material with 8% cobalt boosts toughness and heat resistance compared to ordinary HSS. TiN coating preserves surface hardness and reduces friction for longer service life. 135° splitpoint design provides immediate, accurate engagement to reduce walking and improve hole placement. Balanced combination of wear resistance and toughness suited for both workshop and production environments. Usage notes Use appropriate drilling speeds and feeds for the material being drilled to maximize life and performance. Secure workpieces and clean flutes periodically when drilling dense woods or metals to prevent clogging and overheating. This 4.9 mm M42 cobalt drill bit pack is a durable, precise choice for woodworking, metalworking, and plastic drilling tasks where accuracy, heat resistance, and extended tool life matter.