3/8'' Shank..Quick change chuck
These chucks accept any standard 1/4" Hexagon shank tool. Simply slide the sleeve back to release the tool or to install another. A ball detent system keeps the tool firmly in place so it cannot come out unless physically slide back the sleeve.
You never need to use a key! Just slide back and switch tools. With the Hexagon shank drills or Drill/Countersinks and driver bits they really save time and money. The ball detent holds the tool firmly and it does not wobble. The 3/8" shank has three flats for your chuck to lock onto making it impossible to slip.