Weight: 870g Accuracy: 0.005 HRC: 45-50 100% new high quality. quenching hardness is 45-50HRc. Mount to of backplate to use on a lathe. Can also be used as a fixture on a milling table. Concentricity is 0002 inch colour:Silver Material:High-carbon steel Size: 48x100mm/1.89 inch x3.94 inch Package Contents: 1 x 100MM Diameter ER32 Collect Chuck Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.