These bats are for younger players looking to start swinging wood bats in our Adult models, but in a lighter weight (- 5, - 4, weight). The weight of the bat is called the drop. To figure the drop, take the length of the bat minus the drop and that is the weight, so a 31" length with a -5 drop would weigh 26 ounces, a 31" bat with a -4 drop would weigh 27 ounces and so on...These bats are made lighter for better control and feel when a player is transitioning from metal to wood. All bats will come cupped. Cupping the end of the bat enables us to achieve the weight you ordered, Cupping also transfers the weight from the end of the bat down towards your hands.