Remember when you had the perfect chuck? Secure your bits with the WEN 1/2-Inch Keyed Drill Chuck. Our MT1 arbor taper fits perfectly into any MT1 drill press, lathe, or mill and can be installed with the simple tap of a rubber mallet. The included key securely opens and closes the 3-jaw-chuck around drill bits and shafts up to 1/2 inch in diameter. This set was designed specifically for either the headstock or tailstock of the WEN 8-by-12-Inch Mini Wood Lathe (models 3420, 3420T, and 3421).