Item Type: Trimmer Extension Rod_x000D_ Material: Cemented Carbide_x000D_ Optional Milling Cutter Extension Rod: 1/4 Shank, 1/2 Shank, 8mm Shank_x000D_ Optional Weight: _x000D_ 1/4 Shank: Weight: 107 g / 3.8 oz(approx.)_x000D_ 8mm Shank: Weight: 84 g / 3 oz(approx.)_x000D_ 1/2 Shank: Weight: 131 g / 4.6 oz(approx.) 1Made of high quality hard alloy, high hardness, high strength, not easy to break. 2With extremely powerful clamping force to ensure stability during using. 3Can extend the distance between the edger and the drill bit of the engraving machine, making the engraving distance more suitable. 4Extend the shank length of router bit and make your woodworking project more flexible. 51/4 shank, 8mm shank and 1/2 shank for your choice, easy to use.1 x Extension Rod