When inhaling, I feel a slight resistance; what is causing it?

For the first time, our AMEO FRESH AIR SYSTEM provides the swimmer with fresh air – in contrast to traditional snorkels. The POWERBREATHER uses a membrane, which in the beginning can cause slight resistance when inhaling. However, after a few units the swimmer gets quickly used to the POWERBREATHER. Our membrane not only protects the POWERBREATHER from water penetrating, but already during “normal” swimming provides additional, positive training stimulus for the respiratory muscles.