As you train, gradually increase the weight of the ball as you increase the strength in your pitching arm Color coded cover indicates the ball weight Complete set of six weighted baseballs One each weight 7 oz., 8 oz., 9 oz., 10 oz., 11 oz. and 12 oz. Warning Weighted balls should be used with caution and with proper supervision and instruction. The seller hereby expressly disclaims all warranties, either expressed or implied, including any implied warranty of merchantability or fitness for a particular purpose.