- Chuck key diameters: 3/4 inch (20 mm) / 5/8 inch (16 mm) / 1/2 inch (13 mm) / 3/8 inch (10 mm) / 1/4 inch (6 mm) / 5/32 inch (4 mm); compatible with different types of drills. - Material and finish: Made of solid carbon steel with a durable coating; anti-rust, non-slip design; reduce stress damage within a certain limit. - Storage and use: The small key allows easy storage and use; ideal tool to hold drill bits in place. - Easy to use: The drill clamping key is comfortable to hold; the chuck can be tightened and loosened; convenient for bit replacement and helps reduce stress damage within a certain limit. - Applications and scenarios: - Use with keyed chucks on cordless or mains drills to secure bits before drilling. - Ideal for quick bit changes in woodworking, metalworking, and plastic drilling. - Keeps the drill bit aligned and held in place during maintenance or routine workshop tasks.