Breathable back – and front - The back of this t-shirt is covered by a highly breathable, moisture-control mesh fabric that lets you feel free and never restrained while you’re in movement. Fast-dry front - It’s one of those things that once you have it, you can’t be without it. The tear-proof front of the Performance-T has been engineered with fast-dry, high-tech fabrics that shield, dry and protect. Technology-T - Swiss Engineering – that’s what we call it when all of these different features can be brought together to work in harmony. All taped. All seamless. All engineered for your run in one. Staying fresh - The fabric of the Performance-T is created with specialty treatment that you notice on long runs and short, allowing you to feel fresher both on your run and after it.