Flyer it is a cam lock boat plug. it installs from the inside, so what you see in the pic is the wet end of the plug. It is possible, but not likely, that it will snag on something. From the outside, I would have to hit a stick or something just right for it to push the plug out of its hole. From the inside, there's nothing to cause the cam to unlatch, and something would have to get wrapped around the rear axle inside the tub in order to snag it and pull it out.