T-shirt, MLB, Baseball, Boston Red Sox, 2007 World Series Champions, Majestic Authentic Collection, 90% cotton, 10% polyester, made in Honduras. Tagged as a Size M, Medium. Sizing often varies between brands. Please note these actual measurements. Measuring laying flat: Armpit to armpit = 20.5 inches. Measuring down the center of the back, not counting the collar band = 27 inches. Pre-owned item in good condition, decal/decoration with light wear, no holes, no tears, no stains.