1" x 8 tpi Bottle Stopper Chuck with Pilot Hole Drill Bit. Designed To Mount A Bottle Stopper Blank To Your Lathe Without Using A Jaw Chuck. 3/8" Fits 3/8" Bottle Stopper Blanks. Specifically designed to mount a bottle stopper blank to your lathe without using a jaw chuck. It also has 3/8" stem to fit 3/8" bottle stoppers. The Bottle Stopper Chuck threads directly onto your lathe allowing you to easily mount your bottle stopper blank. After the blank is drilled with the included 11/32" brad point drill bit, it simply threads onto the chuck and is ready to be turned. Ideal for 3/8" bottle stopper projects and for the perfect fit into wine bottles. Chuck threads directly onto your lathe and blank threads directly onto the chuck. Includes; 1 each 1" x 8tpi botttle stopper chuck and 1 each 11/32" brad point drill bit