Trail running, Daily training Front/Back upper panel: 100% Nylon Front/Back lower panel/Side panels/Sleeves: 91% Polyester, 9% Elastane Front/Back upper lining: 100% Polyester Front and back panels feature hollow-core yarn with a unique octahedral structure that traps extra heat, offering superior breathability and lightweight warmth compared to standard fleece. The outer layer is overlaid with lightweight nylon for targeted wind protection and moisture blocking. Main body utilizes Kailas' proprietary POLARMATE stretch fleece fabric—lightweight, highly breathable, and moisture-wicking for comfortable warmth without restricting movement. Athletic cut and ergonomic tailoring ensure uninhibited freedom of movement, making it ideal as a mid-layer paired with an outer shell jacket. Left front chest concealed zippered pocket—practical and convenient for storing small personal essentials on the go. Fit: Regular Fit