smashed my finbox last year, the front screw pulled down and split the box ,the back of the fin smashed the back of the box out, since then i have sleeved all of my boards with some plastic tube and used smaller head screws with nylon washers so if if you hit a rock the screws will shred the tubing, other wise if you use big washers and big head screws you can loose the back of your board , what else does every one else use to stop the damage, eg fast run out tides and coral reefs