Mons Royale M's Olympus Half Zip Ultimate warmth. Designed for the coldest days and the biggest adventure. Olympus is our warmest baselayer offering unrivalled warmth to weight ratio and strategically placed mesh panels to ensure breathability. We use midweight 250 merino wool with added elastane so that Olympus will keep its shape and last longer. Features Half zip for ventilation Raglan sleeves for ease of movement Merino mesh underarm panels Flatlocked seams to prevent friction Thumb loops Slim fit Material Fabric: Merino Blend Weight: 250gsm Blend: 97% Merino Wool 3% Elastane What's sustainable? ZQ Certificate   Non-mulesing Merino wool ZQ is a hallmark that certifies a farmer is meeting the highest standards in the areas of animal welfare, environmental care, and social sustainability - e.g. traceable, No mulesing, Hand selected Environmentally friendly dyes and water processing & fair manufacturing process