Bat Standards
The stamp on the barrel decides where a bat is legal.
How it actually works. Little League requires the USA Baseball stamp for most divisions; most travel organizations, USSSA included, use the USSSA 1.15 BPF stamp, which permits more trampoline effect off the barrel. Big barrel diameter and drop weight limits vary by division as well.
Why it is done, and when it is wrong. This is the single most common piece of equipment confusion in youth baseball, and it gets bats removed from games at tournaments. Read the stamp on the barrel against the rules of the specific league before the season, not at the gate.
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