The vent cap is located on the handle.The vent plug rfgulates air pressure contained within the paddle boards' water tight skin.Regulating the internal air pressure of your paddleboard is the most important maintenance task.Opening the vent cap allows air to escape freely to avoid over pressurization.Neglecting the air vent maintenance may compromise the integrity of the water tight skin or cause severe delamination.Leaving the air vent open while in use will allow water and moisture to enter the foam core resulting in a heavy, "waterlogged"paddle board.