Seirus Thermax Skull Liner
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Ideal for cool-weather starts, slip the Seirus Thermax skull liner beneath your helmet or pack it as a minimalist beanie for light and fast adventures.
For moisture-wicking comfort that keeps your head dry and warm, wear the Seirus Thermax Skull Liner under your helmet or hat. Ultrathin Thermax for moisture-wicking warmth and dry comfort. Flat-seam construction for a smooth, comfortable fit. Lightweight skull cap for versatile wear alone or under a helmet or hat