INCREASE ARM STRENGTH AND VELOCITY: This set includes 8 weighted balls with raised seams, designed to help players build arm strength and improve throwing velocity. Ideal for all skill levels, from beginners to advanced players and professionals, these balls are perfect softball training equipment for athletes PROGRESSIVE WEIGHTS: Includes 8 weighted softballs in varying weights, 4, 5, 6, 8, 9, 10, 11, and 12 ounces. Perfect for progressive training to build arm strength, enhance throwing mechanics, and improve overall performance for players at all skill levels DURABLE CONSTRUCTION: Constructed with a durable genuine leather cover for a real softball look and feel, the weighted softballs are dependable all season. These softballs are not meant to be used for hitting and are only for training purposes REDUCE THE RISK OF INJURY: The various weights allow players to focus on building arm strength and proper form to lower the risk of injury. The progressive weighted training balls are great for all positions including pitchers. INCLUDED THROWING PROGRAM: The included 8-week throwing program will break down specific drills and a number of throws to help players reach optimal levels of performance. When not using the weighted balls with the throwing program, use during warm-ups or cool-downs after games This set includes 8 weighted balls with raised seams, making it essential softball training equipment for athletes. Designed to build arm strength, improve throwing mechanics, and enhance overall performance, PoweNet's Progressive Weighted Softball Set is suitable for players of all skill levels, from beginners to professionals. Use the included 8-Week Throwing Program to focus on specific drills or use the weighted balls for warm-ups and cool-downs.