I had to countersink some screw heads in wood (5/16" screws). No standard trowel will drill a clean countersunk hole for something like a bolt anymore. All are very aggressive and tear the tree to shreds. I think this is the only bit on the market that still makes a clean recessed hole. It doesn't have those flared endpoints (whatever) that all other bits have that pierce the outside edges of the hole and further maim the wood as it cuts. Just the opposite. This bit has pointed edges as you can see in the picture. And coincidentally, the remaining flat bottom of the recessed hole in front of the cone is perfect for a washer for a 5/16" bolt. It must have been made for this purpose. And a socket wrench fits easily in the hole to turn it (Note, to reduce even more aggressiveness when pulling in, pre-drill a small pilot hole so the center of the paddle doesn't want to be pulled further into the wood. This gives you good control over the rate of descent. Don't drill a large one hole, otherwise the drill will wander everywhere.)