【Premium Chrome Vanadium Steel】Crafted from high-strength chrome vanadium alloy steel, this bit holder set offers excellent hardness, wear resistance, and long service life. Built to withstand frequent use in demanding working environments. 【Short & Long Combination】This set includes two short adapters and two extended adapters, providing flexible options for different working positions and improving accessibility in various applications. 【Secure Bit Holding Design】Engineered for firm and stable connection between 1/4 inch drivers and 4mm micro bits. Ensures precise fit and reduces wobbling during operation for improved accuracy. 【Wide Compatibility】Designed to convert standard 1/4 inch hex drivers to 4mm micro bits. Suitable for use with electric drills, manual screwdrivers, and precision tool sets for electronics, furniture assembly, and maintenance tasks. 【Practical 4 Pack Set】Includes 4 silver hex adapters to meet daily replacement and project needs. Ideal for DIY enthusiasts, technicians, and workshop professionals seeking reliable screwdriver bit holder solutions., Manufacturer: Elenviorina