Use with any router table or any router lift to give you the cutter height you need and convenience you will love; includes 1/4 to 1/2 adapter and hex key;Short length and massive body eliminate deflection found with other extensions;Dynamically balanced and machined from fatigue proof steel allows running larger cutters;Quickly change cutters from above the table with a quick 1/4 turn of the wrench;No need to search for your spindle lock or use a pair of wrenches to change bits again