Toolholder bushings are designed with an elongated slot and can be used with most CNC lathes. High universal and can be used for several set screw configurations. Used to adapt boring bars, drills, reamers and shank type tools. For CNC, turret & chucking machines. Measurements are posted in the pictures. Please feel free to reach out with any questions you may have. I will do my best to answer your questions and can provide more pictures if need be. Priced low to sell fast. I have so much that I can’t keep up with posting it. Thank you for your interest and support.