Material:80% Nylon, 20% Spandex FAT BURNING ASSISTANT - Shaping your chest, waist and stomach, it is designed for men and women.When you gym or swim, it not roll up and stay in place pretty. And it is specifically designed to reduce the appearance of Gynecomastia or "man boobs". Breathable for improving blood circulation and fat burning, and strongly chest shaping. It helps with back support and posture. It has been visually being losing belly or chest fata and it does flatten the breast and stomach. LOOKS THINNER AND KEEP FIT - Get your self-esteem back We understand the anxiety some men experience who suffer from these conditions. Our compression shirts for men are specifically designed with these men's self-esteem in mind. The comfort yet practical design of our undershirts provide immediate slimming effect while wearing it underneath all types of clothing. If you want a better body sculpting effect, it is recommended to buy a size smaller, and if comfortable effect, a larger size. REVOLUTIONARY SLIMMING UNDERGARMENT - High quality nylon to stay shaper. Made for wearing underneath any kind of clothing, such as workout shirts, t-shirts, sweaters and formal dress shirts. The slimming compression is a secret between you and your garment. A chest flattening breakthrough This is an excellent Gynecomastia or "man boobs" compression shirt for the man who wants to enjoy a healthy looking figure without the need for surgery or medications.