Bit does not have to be centered in the wood. Simply raise or lower the bit 3/32" to route the mating edge. Cuts all composition materials, plywoods, hardwoods, and softwoods. Use on table-mounted portable routers.
This bit is ideal for gluing edges. I also use cookies for more strength. Cut out a cookie cutter after using this bit. I've found that you want the cookie to be one size smaller than the slot you're cutting. For example, cut a #20 slot and use a #10 biscuit. You will need to raise or lower the cutter 3/32" for the mating surface. This needs to be VERY accurate or your boards will not fit properly. I have a router jack that does this with a washer. This creates a very strong connection. .
Pros
The nozzle does not need to be centered on the tree.