Lightweight stretch jersey gives the Nike Race Day Sleeveless Muscle Top sleek running appeal. Nike Aerographic mesh back panel provides added breathablity and an ultra-lightweight feel. Ergonomic seaming forms to a runners contours for optimal fit. Reflective Swoosh design trademark at the left chest and upper back adds visibility at dawn or dusk. Dri-FIT® 88% polyester/12% spandex with 100% polyester mesh and 93% polyester/7% rayon back panel. Imported.