Vent Screw for Windsurf Board
If you have a board that has a vent screw, you want to make sure you have extras! The vent screw, or vent plug, is usually located just in front of the mast track and is used to equalize pressure in the board. The screw should be loosened when the board is changing elevation (going on an airplane or driving through the mountains) or when there is a chance that the board will get so hot that any air inside might expand. When it's time to put the board in the water, you want to tighten the screw. If you sail the board without the screw (or with the screw loose) water can get inside your board - and that is no good! Aluminum screw with O-Ring.
Buy a couple of these and keep them in your car!