Abstract: An adaptive device for use as a tool holder for manual and computer numerical controlled lathes is provided to retain and use tools of various sizes, including those intended for use on CNC lathes and on mills. The device includes a sleeve, which includes an inner-tapered surface, a neck and an opening, and a threaded member sized to fit through the neck in the opening. The adaptive device may further include one or more shoulders and/or grooves on the exterior of the sleeve, and/or a retaining member fitted to the threaded section, and may include an embodiment where the sleeve is integrated into a tool holder and/or where the threaded member is constructed to permit fluid flow into the tool holder.