"The Rab Merino Beanie knits superfine 100% merino wool into a beanie light enough to forget we're wearing it, yet warm enough to hold onto heat on a cold hill or mountain day. A self-fabric hem keeps the construction simple, so the beanie layers as easily under a hood as it does on its own. What Our Gearhead® Experts Are Saying:""I keep this in my pack for belays and lift lines because the stretch fit sits close enough to pull a helmet on right over it without any extra bulk at the temples."""