Ok lets just call the nanoflex arm warmers magic warm and wind resistant in the dry when it rains water just beads away we always strive for total performance and total innovation but sometimes we surprise ourselves this nanoflex fabric behaves just like our thermoflex fabric in dry conditions but then provides unbelievable water repellency when it starts raining we dont claim that its fully waterproof but its the most effective thing weve ever made for keeping you comfortable in all c