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Ideal for cool-weather starts, slip this liner beneath their helmet or parka for added warmth. Ultra-thin Thermax(R) polyester with a bit of Lycra(R) spandex stretches to fit, wicks away moisture and dries quickly to maintain warmth. Flat-seam construction and four-way stretch improve comfort. Reversible design: chose from exposed contrast stitching on one side or solid black on the other side.