Check the listing for details. Threaded adapter join multiple rotary tool flex shafts together. Longer cable. Color: Silver, Condition: New. Listed at 28.00 USD. The following item (threaded adapter to increase the length of most powered hobby tool Flex Shaft), was developed to extend the usefulness and length of the tool. Extends life of flex shaft by reducing the bend radius of cable. The internally and externally threaded adapter connects multiple Flex Shafts together to extend the working length of the tool. The machined flat areas on the 3/4 externally threaded diameter are for tightening the threaded adapter, with a 5/8 open end wrench,to the 1/2-20 male thread under the internally threaded cap of the Flex Shaft Handpiece. The cap will not be used in this assembly. Complete the connection of the second Flex Shaft as you connected the first Flex Shaft to the power tool.The two notches on both sides of the threaded adapter are intended to help remove the adapter if it gets stuck in the housing nut due to improper installation. A penny works as the wrench. Buyer must purchase the second Flex Shaft at a place of your choosing. Cost Approx. $28.00