The Rockler Router Bit Center Depth Gauge allows users to quickly set their router table fence a precise distance from the center of the bit, says the company. It also works as a depth gauge for bits and blades and for routing dados and flutes. Half-round notches register a user’s measurements to the center of ¼” and ½” shank bits. It allows users to measure the bit height through the hairline indicator for the desired depth of cut, adds the company. The 12” steel ruler features metric and imperial measurements.