Lululemon long sleeve workout top with cute mesh cut outs on the back and side No tag but this is a 4 From tag: This lightweight, cool-feeling long sleeve gives you breezy coverage for any and all of your sweaty endeavours. Mesh fabric panelling on the back gives you the airflow you want, without having to remove a layer. Sweat-wicking fabric is four-way stretch • added Lycra® fibre for stretch and shape retention features • Designed for: Run • Breathability: Strategically placed Mesh fabric provides ventilation • Relaxed fit, hip length: Layers easily and gives you room to breathe Style Number: W3BGCS