Arc'teryx Calvus Cap Spacermesh Polydel Mesh - 100% polyester 3" high 8" wide CALVUS CAP - Designed for mountain training across a range of conditions, the Calvus Cap provides sun protection, water resistance, and moisture management on the move. FABRIC - The Socora polyester fabric is light, air permeable, and wicks moisture. Polydel mesh side panels and the Spacermesh sweatband add next level comfort, and a DWR (durable water repellent) treatment adds a layer of protection from light rain. The adjustable stretch closure strap with a low profile quick release buckle secures the fit without binding. RUNNING SYSTEMS - Technical trail running systems with a focus on freedom of movement and moisture management. BREATHABLE MATERIAL - Allows moisture vapour to escape, helping regulate temperature and elevating comfort inside garment