Keyed Chuck
Affiliate link — we may earn a commissionA keyed chuck uses a small T-handled gear key that meshes with teeth on the chuck ring. You insert the key into one of three holes on the chuck body and turn it to tighten or loosen the jaws. Keyed chucks grip harder than keyless chucks and don't slip under heavy loads, which is why drill presses and some corded drills still use them. The trade-off is speed: bit changes take 10 to 15 seconds instead of 3 to 5, and you need the key. Lose the key and you can't change bits. Most people wire-tie the key to the drill cord or keep one in a pocket.
Why It Matters
For drill press work or any situation where the bit must not slip (large hole saws, heavy boring in metal), a keyed chuck gives you the tightest grip. For a cordless drill on a job site where you're changing bits constantly, keyless is faster. Match the chuck type to how you use the tool.