Designed with 1/4” [0.6cm] shank for use in Jacobs type chucks.This tapered chuck is built to accept small buffs, brushes and lead-centered wheels. Made of alloy steel and plated. Unit Dimensions: 2 5/8” L x 1/2” Shank Diameter [7cm x 1.3cm] with a 1/4” Shank Diameter.