Rock America Rock T-Shirts are highest quality, licensed band t-shirts. Most of our band t-shirts are 100% cotton and preshrunk for a quality fit. They’ll hold up to the toughest mosh pit! We have the latest designs and rock logos on our t-shirts, as well as rock t-shirts in classic designs that have stood the test of time. Def Leppard Adrenalize T-shirt. Official short sleeve Def Leppard T-shirt.