Best-selling ActiveIce technology is upgraded for Spring 2021 to work more efficiently and effectively than ever before. Now featuring the same thermo-regulating formula as OR's proprietary ActiveTemp, this new version of ActiveIce dynamically adjusts to your body's temperature to cool you faster when you need it most. Still wicking and complete with a UPF 50+ sun protection rating, ActiveIce is a great companion for anyone who spends serious time in hot, sweaty, sun-baked conditions. The ever-popular Outdoor Research ActiveIce Sun Sleeves are an easy solution to pull-on sun protection, with bicep grips to hold them in place.