The adidas Speed Striking Balls are designed for intense boxing workouts, featuring a convenient lace-up closure and a changeable valve bladder. Made from high-quality cowhide leather, these balls are built to withstand rigorous training sessions. The latex bladder may naturally lose up to 20% of its air within 72 hours. Model: ADIBAC09 Sizes: Small = 23 x 15cm Large = 25 x 18cm