This is a KNOW WAVE t-shirt. Size M, brand new, unused. If you have any questions about the condition or anything else, please feel free to ask. I bought this for myself but am selling it because I won't be using it. Even items listed as new have been handled by someone, so if you are very particular or have any concerns, please refrain from purchasing. To prevent product substitution, returns, refunds, or exchanges will not be accepted for any reason. I want to ensure a smooth transaction for both of us, so thank you for your understanding.