Features of the Icebreaker Men's ImPulse Training 7 Inch Short Air permeable Pertex Quantum air nylon fabric for breathability and optimal comfort in all conditions Cool-Lite long liner for faster wicking Corespun fabric for enhanced durability Internal Cool-Lite lined waistband for faster wicking and comfort Waistband with internal drawcord for adjustability Zippered hand pockets Icebreaker reflective heat transfer logo Fabric Details Main: 48gm Pertex Quantum air 20 denier/100% Nylon with DWR finish Mesh Lining: 145gm Eyelet Corespun, 51% Merino, 34% Tencel, 15% Nylon