Premium Material: Made of high quality material, durable and convenient to use(Please receive the coupon code on the product page when purchasing to get a cheaper price.) Wide Usage: Suitable for automotive manufacturing, mold making, machinery manufacturing, etc. More Safety: Eliminate the dangerous temptation to pull out the collet shank, extend the bit to get the full depth of cut. Safety Notice: The extension shank should be tight, but the collet nut should only be tightened only with the same pressure as any router collet. Please note that the extension rod should be well cooled, but the collet nut should only be tightened with the same pressure as any router collet Attention:Make sure the router clamp extension is properly assembled.Please note that the extension rod should be tight, but the collet nut should only be tightened with the same pressure than any router clamp. Specifications: Material: Hard Alloy Color: Black Stem Diameter: 8mm Hold Diameter:8mm Overall Length: 86mm Contents: 8mm Router Collar Extension Weight: 84 grams Quantity delivered: 1 piece