Guardian manufacturers a limited amount of PEARL X NFHS stamped lacrosse balls. PEARL X balls PEARL X, PEARL LT, and PEARL DUAL X balls are all SEI certified to meet NOCSAE/NCAA standards for game play and are stamped with NOCSAE/SEI certification markings. We also manufacture PEARL X white and yellow balls that include the NFHS stamp, if requested by a team. All balls can be used in practices, but some high school teams may require NFHS stamped game balls. NFHS balls include an additional fee charged by the NFHS for their marking. All X balls are identical in composition and specs, and all LT balls are identical in composition and specs, regardless of their markings.