Get precision gripping and centering of small diameter dowels and tenons. Ideal for gripping pen mandrels, bottle stoppers and other small projects where a tenon is used for chucking. Easily hand tightens to safely secure collet and workpiece. Pre threaded with 1" x 8 tpi headstock thread. The complete system includes a 3/4" x 16 tpi spindle adapter, with collet closing head, 5 collets: 1/4-Inch, 3/8-Inch, 1/2-Inch, 5/8-Inch, 3/4-Inch, and a blow-molded carrying case for easy storage.