Slam balls are designed to have no bounce. These are great for working out your entire body and taking out aggression. These slam balls are made to take the abuse. This extremely durable rubberized slam ball comes in 5lb increments starting at 10lb and ending at 50lb. The diameter for this slam ball comes in two sizes. 10lb-30lb is 9Ó diameter while 35lb-50lb is only increased to a 10Ó diameter making these easy to handle for any size athlete.