Klein Tools 3/16 in. x 54 in. Extension Flex Auger Bit 53723 - The Home Depot
Fulton 10 inch Long Forstner Bit Extension for Adding Over 8" of Drilling Depth to Your Forstner Bit Ideal for Wood Turners Furniture Carpentry and Construction (3/8 inch Collet) - Amazon.com
Drill Bit Extension Set Hexagon Bit Extension Rod Conversion Rod Impact Long Bit Extension Bit for Furniture Carpentry , 300MM - Walmart.com