Deckel collets for the single-lipped cutter grinder models SO and SOE. 20mm shank diameter, with Deckel 20x2mm butress mounting thread. Maximum thru bore 0.513 inch (13mm). Seven of the most popular inch sizes make up this standard set normally sold together with a new grinder: 1/8", 3/16", 1/4", 5/16", 3/8", 1/2", and 5/8" diameters. Made in Germany. These collets will also fit the Kuhlmann, Hassberg, Alexander, and Pregraph cutter grinders.