Made of food-grade Silicone, the Aquacom easily and unobtrusively installs over your helmet’s existing microphone. Simple design makes for easy removal, cleaning, and replacement. Audio fidelity remains crystal-clear, with users able to keep the microphone foam on for install. The Aquacom Pro is the smaller of the two sizes, designed to work with a variety of microphone sizes. This replacement pack comes with 1 Aquacom Pro.