There are instances wherein a baseball bat has been certified by USSSA, even already having a stamp of approval on the bat, only to see it become ineligible after further checking by the governing body. To make sure the bat you intend to use or have been using is still legal or allowed, you can peruse the USSSA Banned Bats List occasionally. Additionally, a Senior League bat is also USSSA-certified, however, it is only allowed and used in kid-pitch leagues.