Primal Lightweight Sun Sleeves are built using Lightweight Priflex fabric, a lightweight compression material that provides coverage on your arms from the sun's damaging rays. An anatomical design with silicone grippers at the bicep prevent slippage and maintain flexibility. They’re adaptable to rapidly changing weather and use less space when rolled and stored in pockets. https://www.primalwear.com/collections/cycling-accessories/products/colorado-lightweight-sun-sleeves?variant=40888446713936