Intermediate (50-70) Division and Junior League:
It shall not be more than 34″ inches in length; nor more than 2⅝ inches in diameter, and if wood, not less than fifteen-sixteenths (15/16) inches in diameter (7/8 inch for bats less than 30″) at its smallest part. Wood bats taped or fitted with a sleeve may not exceed eighteen (18) inches from the small end.
NOTE 1: Solid one-piece wood barrel bats do not require a USA Baseball logo.
NOTE 2: Also, permitted for the Intermediate (50-70) Division and Junior League Division are bats meeting the BBCOR performance standard, and so labeled with a silkscreen or other permanent certification mark. The certification mark shall be rectangular, a minimum of a half-inch on each side and located on the barrel of the bat in any contrasting color. Aluminum/alloy and composite bats shall be marked as to their material makeup being aluminum/alloy or composite. This marking shall be silkscreen or other permanent certification mark, a minimum of one-half-inch on each side, and located on the barrel of the bat in any contrasting color.
Additional details can be found on the Little League Bat Rules page