Using these breathable reusable filters our team found that they were perfect for outdoor sports and activities .They were comfortable and easy to use, and we were able to breathe easier during our climbs. The filters also prevented dust and debris from getting into our lungs, which improved the overall experience of our trek. However, the only downside we experienced was that the filters needed to be washed frequently, but this is a minor issue. Overall, we highly recommend these filters to anySee full review