A unique 2-in-1 base layer with 100% merino wool exterior and 100% LIFA Stay Warm Technology interior LIFA: LIFA is the original Helly Hansen base layer made of 100% LIFA fibers, providing warmth and insulation in cold weather. LIFA naturally pulls moisture away from skin and to the outer layer of the garment keeping you warm, dry and comfortable. FEATURES: 2-layer construction, 100% Merino Wool exterior, 225g LIFA Merino fabric, Non-itch, Flat lock seams GOOD FOR: Camping & Hiking, Climbing & Mountaineering, Trekking, Resort, On Piste, Alpine, Winter, Skiing FIT: Regular - Neither slim nor oversized. Regular-fitting garments may be worn over thicker midlayers. Pants will have a standard inseam with a cut that's straight through the leg.