A finger joint, also known as a comb joint, is a common woodworking joint made by cutting a set of complementary, interlocking profiles in two pieces of wood, which are then glued. KOWOOD Finger Joint Bit can cut perfectly for joint. It comes withbearing for guide it to cutting correctly. 1. Always wear eye protection 2. Always using safety cover provided by benchtop router table 3. Do not wear gloves to avoid hazard of getting caught in the tool and pulling your hand in to get mangled during bit spinning 4. Examine the bits before use for cracks or chips. Do not use damaged or bull bits. 5. Make sure bits are properly secured in collect and reach the indicator mark (“K” Mark) 6. This product is designed for benchtop router machines only. Please do not use in another machine (etc. Driller) 7. Max. Rpm in 18000 Note: 1. Determine the size of the wood and adjust the height of the finger joint before cutting, also suggest the testing piece before the actually cut to ensure fit. 2. Please don't change other size of bearing. 3. Make sure the bearing is on securely and can spin freely. 4. Set the fence so it aligns with the guide bearing for the router table. 5. Turn on the router and carefully make the cut. recommand in table-mounted router, keep the workpiece against the fence as you advance it past the bit.