The Ionia&&';;s performance is innate. Made from Merino wool - a material known for temperature regulation and odour resistance - it&&';;s light, soft, breathable, and responsibly sourced. The construction wraps the wool&&';;s fine-gauge fibres around a nylon core for added durability. The fit is streamlined and comfortable, and the articulated patterning moves with you on hikes, runs, tours, and treks. Crafted at a Fair Trade Certified(TM) facility as part of our commitment to transition 80% of Arc&&';;teryx products to Fair Trade Certified by 2025. Features & Specs Technical features Breathable Lightweight Versatile Natural merino wool has anti-odour properties Air permeable Construction Ultra fine Merino wool is known for soft comfort, natural temperature regulation and odour resistance Merino fibres are wrapped around a nylon core for added durability Cuff & Sleeves configuration Short sleeves Logos & Label configuration Arc&';teryx Bird logo Neckline configuration Crew neck Patterning Articulated patterning for unrestricted mobility Sustainability Contains wool certified to the Responsible Wool Standard (RWS): RWS is a voluntary program that helps sheep farmers meet consumer, retailer, and brand demands. The standard certifies they meet rigorous animal welfare and land management requirements. RWS (Responsible Wool Standard) - The wool in this product is 100% Responsible Wool Standard (RWS) certified by IDFL (No.TE-99950273) PFAS (Per- and polyfluoroalkyl substances) Compliant Size XS, S, M, L, XL, XXL Weight 155g / 5.5 oz Fit Fitted Activity Hike/Trail Run Model X000006816