PREMIUM MATERIALS - Constructed from industrial grade chromium vanadium steel, this 20-piece non-magnetic nut driver set is built to last. The black phosphate coating ensures superior corrosion resistance, making it perfect for long-term use in any environment. VERSATILE SIZE RANGE - Includes 10 metric sizes (4mm to 12mm) and 10 SAE sizes (5/32" to 1/2"). This extensive range makes it an ideal tool kit for various applications, from household DIY to professional mechanical work HEAT TREATMENT TECHNOLOGY - Undergoes complete high-temperature quenching, achieving exceptional hardness and maximum torque resistance that ensures long-term durability for professional workshop use and heavy-duty applications. CLEAR IDENTIFICATION - Each impact nut driver has clearly marked sizes for easy identification. This feature saves you time and increases efficiency, allowing you to quickly find the right tool for the job without hassle. PORTABLE PACKAGING - Features a compact storage base with carabiner clips that securely fasten to tool belts and bags, making this nut driver set perfectly portable for professionals on the move who need quick tool access at multiple job sites., Weight: 0.6834330122 pounds, Manufacturer: SWANLAKE GARDEN TOOLS