Size - Magnetic hex ball end screwdriver bit size: 4mm (H4.0); hex shank size: 1/4 ; total length: 200mm / 8 ; hardness: HRC56-58. Each hex screwdriver bit is clearly engraved with the model number for easy identification. Material - The metric ball end hex screwdriver bit is made of S2 steel with high strength and wear resistance, anti-bending, anti-breaking, not easy to deform, and durable. The chrome-plated surface is bright and shiny, effectively preventing metal oxidation and corrosion, enhancing hardness and wear resistance for better scratch resistance. Feature - The ball end hex bits are designed with magnetism, which can stably absorb the screws vertically or tilted and easily fix the screws, especially in a small space, which can make it more convenient to complete the work. Application - The metric wrench screwdriver bit is a good helper for removing or installing screws, and is used in such as furniture assembly, mechanical equipment installation, car repair, home DIY projects, homemade furniture, building woodworking structures, etc. Widely used in manual electric screwdrivers, drills, and electric drills. Note - Check whether the ball end drill bit is firmly installed on the power tool before use. Keep it away from high magnetic and high-temperature environments when storing it to avoid affecting the magnetic effect. ASIN B0D7PNNWCH Set Name HARFINGTON 3-Piece Set Brand Name HARFINGTON Unit Count 3.0 Count Item Length 7.87 Inches Drive System Hex Finish Types Chrome-plated Manufacturer HARFINGTON Material Type S2 Steel Number of Pieces 3 Drive Bit Shank Style Hex Manufacturer Part Number hta240606hh000205