Manufactured to our high standards and attention to detail, will prove to be the best practice balls youve ever used in your machines. 1-Year Guarantee?No one guarantees their practice balls longer! Available in Game-Ball Yellow only, 11 or 12 inch. Specifically designed for use with pitching machines. Dimpled for maximum accuracy and performance. Feels like a leather ball when hit. Will not sting your hitters hands. Same size and weight as leather softballs.