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The REI Venturi tights are there to support you when you feel inspired to run a little farther, climb a little higher or otherwise push your limits a little bit more. Knit polyester/spandex blend wicks sweat and offers 4-way stretch to enhance your comfort as you make your way down the trail; fabric also has good snag resistance. With a UPF 50+ rating, fabric provides excellent protection against harmful ultraviolet rays. Internal waistband ensures a snug fit; mesh venting behind the knee and at back waistband promotes ventilation. A classic rise fits comfortably and a fully gusseted crotch allows full range of motion. Athletic fit means you can layer them under other layers for extra insulation or wear them alone in warmer conditions. The REI Venturi tights feature an external stash pocket for carrying small essentials.