The air vent screw is located on your board. It’s very important because it regulates the pressure inside the board, which can increase with temperature or altitude. If this pressure is not regulated, it can damage your board. It is therefore crucial to open this screw when storing the board, especially in hot places such as a car or a sunny beach. If you have an automatic decompression screw, you don’t need to do anything – the board regulates itself.