Our most popular training shirt ever, made from our updated AeroSilver® fabric. AeroSilver® is the next generation of our silver-infused performance wear, with enhanced durability and fiber strength to endure the toughest training sessions. The shirt is designed with a slim fit and extended hems for added coverage while moving. It features side splits with reinforced tack seams for complete freedom of movement in the side body, and raglan sleeve construction for movement in the arms. Finished with reflective logo details. Model is 5'11 170lbs and usually wears size M. This product fits true to size so he is wearing size M for a slim, performance fit.