There are questions swirling around about legal bats . The following link will take you the USA/ASA website to see a list of legal bats. There is also a list of ASA bats that have the certification stamp, but are not legal
https://www.teamusa.org/USA-Softball/Certified-Equipment/~/link.aspx?_id=015F4358A30B44368FC142350D112FFF&_z=z