Boost Hero sports top made from 100% jersey cotton. The perfect t-shirt for wearing in your free time or underneath your fleece. Available in a variety of different colours, this shirt is lightweight and has a sleek cut. Crew neck. Available in a wide range of sizes, from children's to adults. For Unisex garments in our size guide you can refer to the table with the conversions for men. If the wearer is a woman, please note that the fit is slightly oversized.