Shield Technology perfectly positioned to help protect against sudden impact and minor injuries to the sternum and chest area Padded baseball shirt builds confidence in young baseball/softball players when fielding ground balls and pitching Quick dry technology on this youth baseball chest protector keeps the player cool and dry; 80% nylon/20% spandex with polyethylene foam padding Compression fit mesh design for baseball players but can be used in any sport where you are looking for added sternum protection; Softball, Football, T-Ball, Lacrosse, Paintball, Goalies, Catchers, Pitching and Batting Sizing based on chest circumference: X-Small (23.5"-25"), Small (25"-26.5"), Medium (26.5"-29.5"), Large (29.5"-33"), X-Large (33"-36") The Sports Unlimited Diamond Shield Youth Sternum Shirt was designed to protect against sudden impact to the sternum and chest area. As a young athlete, it is critical that they play their sport with confidence! 10mm Diamond Shield Technology is perfectly positioned and sized for the right amount of coverage and protection. The diamond shield is sized slightly smaller on the Small and Medium shirts versus the Large and XL sizes. This custom sizing is what sets us apart from the competition and allows the player to move freely. Compression fit mesh design for the perfect fit underneath the jersey and added length ensures the shirt stays tucked-in. Wear it in practice and games! Put on the Diamond Shield and watch your little athlete’s confidence soar!