Irwin Speedbor 6 x 1/4 in. Wood-Boring Spade Drill Bit Extension is designed to provide extra reach for your drilling needs. Featuring a double set screw with an Allen wrench, this extension is for all 1/4" round shank drill bits that require additional length. It is compatible with 1/4" shank Speedbor or Do it brand bits and allows you to follow 5/8" and larger bits through holes with ease. This extension measures 6 inches in length and comes in a convenient card package, making it a practical addition to your tool collection. Model Number: 88702