Wide compatibility: This key extender is designed to fit standard hex screws and nuts and connects seamlessly with 1/2 inch or 21 mm hex keys, providing versatile compatibility across tools and fasteners. Applications: Ideal for motor vehicle maintenance and the installation of mechanical equipment; supports professional machine repairs and everyday home repairs; adaptable for various tasks. Time-saving design: The fast plug-in interface reduces tool changes and speeds up your workflow for a comfortable, efficient working experience. Durability: Made of high-strength alloy steel for long service life; excellent wear and impact resistance suitable for heavy-duty industrial use. Use scenarios: Automotive repair and maintenance; installation and servicing of mechanical equipment; home DIY projects such as furniture assembly or bicycle maintenance.