Below is reprinted directly from the BNS Handbook and may be updated as the source is updated
Bat Rule 5.2.6.1 11U - The bat shall be round and made of approved material and shall NOT be more than thirty-two (32) inches in length, or more than 2-3/4 inches in diameter at its thickest part. Bats may be taped to a distance not exceeding sixteen (16) inches from the handle.
5.2.6.2 13U - The bat shall be round and made of approved material … it shall NOT be more than thirty-two (32) inches in length, nor more than 2-3/4 inches in diameter at its thickest part. Bats may be taped to a distance not exceeding sixteen (16) inches from the handle. The bat may have a maximum weight-length differential of -10. a) Cupped Bats. An indentation in the end of the bat up to one inch in depth is permitted and may be no wider than two inches and no less than one inch in diameter. The indentation must be curved with no foreign substance added.
5.2.6.3 15U - In all levels (AAA, AA, A) Only wood bats, bamboo bats and wood composite bats will be allowed. Wood composite bats include wood bats with fiberglass sheathing and wood barreled bats with composite handles. Wood composite bats do not include any bat that has any metallic component. Note: Females playing on all boys’ teams at this level must adhere to rule 5.1.6.3. If the team consists of all female players, they will be permitted to use an aluminum bat with a maximum weight-length differential of -5. There are no restrictions on wood bats.
5.2.6.4 18U, 21U, Intermediate and Senior - In all levels (AAA, AA, A) Only wood bats, bamboo bats and wood composite bats will be allowed. Wood composite bats include wood bats with fiberglass sheathing and wood barreled bats with composite handles. Wood composite bats do not include any bat that has any metallic component. Note: Females playing on all boys’ teams at this level must adhere to rule 5.1.6.4. If the team consists of all female player’s they will be permitted to use an aluminum bat with a maximum weight-length differential of -5. There are no restrictions on wood bats.
5.2.6.5 Colored Bats - BNS permits the use of colored bats, but does prohibit any bat that, in the opinion of the umpires, discolors the ball. Any such bat shall be removed from the game.
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