13-piece cobalt hex drill bit set includes 15, 20, 25, 30, 32, 35, 40, 45, 48, 50, 55, 60, and 65mm sizes with 1/4 inch hex shank. Special plug hex design provides improved performance compared to standard pressed hex, reducing the risk of bit slippage and ensuring a secure fit during impact drilling. Cobalt-containing drill bits offer longer lifespan than titanium-coated bits. Fully ground spiral flute allows for quick chip removal, reduced friction and heat buildup, enabling faster, cooler, and more efficient drilling. 135-degree split point tip prevents walking and ensures precise, stable drilling without the need for a center punch. 1/4 inch hex base fits most drills and drill presses, allowing for quick, easy, and secure installation without slipping or disengaging. Suitable for use on wood, plastic, steel plate (up to 5mm), aluminum alloy, and other soft metals. Ideal for DIY projects, home maintenance, and repair tasks. Not suitable for glass, ceramic, or concrete. Color: Silver. Material: High-speed steel. Package includes: 13 x cobalt hex drill bits. No additional items included. Note: Lighting and display settings may cause slight color variations between the image and the actual product. Measurement may vary by +/- 1-3 cm.