Proton Heavyweight Hoody Men's Created to offer the breathability, durability, and mobility guides and mountain professionals demand, our warmest Proton delivers air-permeable thermal performance for high-output missions in cold conditions. 100gsm Coreloft™ insulation and the Fortius™ Air 50 outer allow airflow that helps speed vapour transport and balance thermal comfort. 60gsm Coreloft™ in the sleeves and helmet-compatible StormHood™ reduces bulk, the regular fit layers easily, and articulated patterning removes restriction. Coreloft™ Continuous 60 - 100% polyester Coreloft™ Continuous 100 - 100% polyester Lining: 20D plain weave - 100% Nylon - bluesign Approved Material