Starting on January 1st, 2018, USA Baseball will adopt a new method for measuring bat performance in the testing of youth baseball bats.
Players will be allowed to use either a 2 and 1/4 inch or 2 and 5/8 inch barrel size bat with a new USABat stamp. Bats without a USABat stamp will no longer be allowed for use in Little League baseball.
UPDATE 9.1.2017 - New bats are going on sale now at your local stores and online. New bat standards are being adopted by Little League, Babe Ruth & Cal Ripken, PONY, Dixie and AABC. If you play in any of these leagues you should not buy any used bat.
2017 approved bats are legal to use through December 31, 2017 - so, yes, you can use the old bats for Fall Ball leagues.
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