Polartec® neck gaiters from Airhole, each with a single Airhole at the mouth. The Airtube Ergo Polartec® Power Dry™ is a bi-component knit that pulls sweat off your skin and dries fast. The flat-top Airtube Polartec® 100 is a light fleece whose raised pile holds warm air, and the Airtube in Polartec® Thermal Pro™ uses our warmest fabric, a deep sherpa-style pile. Sizes S/M and M/L.