Find the right amount of filtering for your level of training/racing effort and your comfort. These two-pack filters allow you to switch out filters from your AirTrim mask so you can breathe comfortably with your preferred level of heating vs airflow. Filters come with 5 levels of filtering. The rolled corrugated plastic in the filters is colored white or blue. The white filtering plastic offers more heating and less airflow and the blue plastic filtering material offers more airflow. The Racing Filters have varying amounts of white vs blue filtering material. The Asthma filter is the most restrictive, warming the air the most. It is made of tightly packed white filter material. The Racing3 filters offering the highest airflow, and are completely made from the blue filtering material. The other filters are in stages between those 2 filters, becoming progressively more open until the Racing3. In a study at the University of Montreal, they found that the AirTrim mask is great for training and low exertion activity. They recommend to use for warming up and easy effort activities. Once you have a race or interval session, it is recommended to remove the mask to allow unrestricted oxygen flow. To read the whole article, head to this link: https://nature-humaine.ca/2023/02/air-trim/. With our personal experience here at Skiwax.ca, we agree with this assesment of the AirTrim Mask. The mask is great for warm-ups, easy skis, and cool-downs, then removing the mask, or having the Racing 2/3 filter for harder efforts will have you feel and perform better.
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