Features of the Sierra Designs Women's Long Sleeve Solar Wind Shirt Lightweight, yet Highly durable 90D fabric will keep you cool and take abuse High-air-flow knit back panel keeps you cooler and drier under a pack and stretches to allow unrestricted movement Knit underarm panels for ventilation and increased range of motion Collar flips up and secures with a hidden button for added wind and sun protection Soft knit lining on collar for comfort on the neck Full snap front completely opens to vent when the day heats up Stretch cuff allows sleeves to push up and stay up without the hassle of fasteners or folding Concealed sleeve pocket for lip balm and sunscreen that won't interfere with pack straps Trim Fit is shaped for ease of movement with dropped hem for extra coverage