The Weighted Balls Carlos Used in Pro Training Weighted-ball training is standard at the professional level — arm-strength development, mechanics refinement, grip feel work. Kachi's weighted training balls are pro-spec: multiple weight variants in a matched set, consistent diameter for realistic grip feel, durable construction that survives thousands of throws. Set Includes Weights: 4 oz, 5 oz, 6 oz, 7 oz, 9 oz, 11 oz (6-ball set) Diameter: Standard baseball diameter across all weights Material: Synthetic leather covering, high-density core Color-coded: Each weight is a different color for easy identification From Carlos "Weighted-ball training was a key part of my development as a professional player. These tools help build the strength and coordination needed for elite performance." — Carlos Castillo, Former MLB Pitcher A note: Weighted ball training should be progressed carefully. Consult a qualified pitching coach before starting a weighted-ball program, especially with youth players. Kachi does not recommend weighted-ball training for players under age 13. Lifetime craftsmanship guarantee · Free US shipping over $150 · Shipped from Miami · Questions: [email protected]