Thread these chucks onto the spindle of portable drills and stationary machines to hold bits. They're a keyed chuck, so they hold the bit tightly, preventing it from slipping under load. Use the included key to tighten and loosen the jaws. If your machine doesn’t have a threaded spindle, mount them with a threaded drill chuck arbor.

To maximize grip and minimize wobble, choose a chuck where your drill bit diameter falls in the middle of the shank size range.

Light duty chucks are small and lightweight, so they're optimized for the low-torque drilling needed for wood and plastic. They have a two-piece sleeve that would wear out quickly from the friction created when drilling in hard materials such as steel.