It covers an enormous cut out chunk of the fiberglass they removed to place the depth sender unit. Every haul, we seem to hit it(this time we hit, then moved to the right place). Every year, I take it off, pound it flat(or get another piece) and put it back on. If it ever gives up, I swear I will glass it in and mount a new sender inside the hull.

Good eye though. The last granite kiss is just below that on the lead keel, if you look closely. That was epic....