keel boat. Nothing gets stuck to the bottom. Not mooring lines, anchor lines, long lines, lobster traps, kelp or crap floating along on top of the water. I've run over them all and nothing, nadda, zip. That's not saying that someday something might not get caught in the prop but nothing in the last 18 years. Maybe I'm just lucky but I don't think so. It just slides down the from and pops up in the wake.