The Easy Wood Easy Chuck 4" (1" x 8 TPI) Woodturning chuck and the Easy Jaw system allow you to change from one set of jaws to the next in about 30 seconds. The patent pending Snap-Lock Technology uses no jaws screws or wrenches to exchange the jaws. You simply use the supplied Jaw Key to depress a keeper latch in the jaw and slide each jaw right out. You then slide in the next jaw type until you hear the cool sounding "Snap". This gets you back to turning quickly with the jaws you need to hang on to your project safely. This chuck is also equipped with a Zoom Ring to allow for Finger-tip opening and closing. The Easy Chuck's Zoom Ring gives you the ability to open and close the chuck very quickly for various gripping diameters with just your fingertips. Use the Zoom Ring to bring the jaws into position to lightly grab your project then use the supplied chuck key for final tightening.