Armor alloy features a matrix material coating, a proprietary combination of metal and ceramic, which is used in jet engines. The metal portion of this ultra hard alloy coating gives you the performance you expect, while the hard ceramic reduces wear and tear experienced in typical play. Louisville Slugger senior league bats are specifically designed for players between 13 and 15 years of age as well as younger players whose leagues allow bat diameters larger than 2 1/4". All senior league bats have the Major League Baseball logo on the barrel. Armor alloy Matrix material coating Power balanced 2 3/4" patented full barrel Patented pro cup end cap Synthetic grip, 7/8" standard handle 05