66fit Slam Balls are weighted balls that are designed to be slammed into a wall or the floor. The no-bounce design enables the user to build explosive strength.FeaturesInner Material: Sand/Iron MixOuter Material: PVCWeight: 15kgColour: BlackDescriptionIdeal for Crossfit, boxing, core strengthening and general fitness - 66fit slam balls are ideal for building up explosive strength, speed, stamina, and improving coordination. So why not take out your frustration and build up your fitness by slamming the balls into the ground!