Big Horn 19081 Router Bit Centering Gauge
Use Big Horn's router bit centering gauge to precisely place your cuts and dadoes. Slip this pin-point precision gauge into your router collet (fits both 1/4-Inch and 1/2-Inch) and every cut will be on target! With your router inverted, hold a square in place and rotate the gauge to check for run out or wobble. 3-Inches long by 1/2-Inch diameter.