My boat has a hole cut into the engine compartment to accept a fire extinguisher in the event of fire. There was a rubber cover over it that rotted away, and I'd like to replace it. It was a very basic, square piece of white rubber that had an "X" cut into it to allow something to be stuck into it (sts).<br /><br />Any idea what this thing is called? <br /><br />I've looked online w/o success and the West Marine guy didn't know what I was talking about...thanks in advance