BOLA 5oz Practice Balls. Polyurethane practice balls in red or yellow with soft case to protect bats from damage. Dimpled like a golf ball for stable flight. These give the best accuracy and realistic bounce. Yellow balls for better visibility indoors. Red for realism.BOLA 3oz 'Orange' Practice Balls. The Orange balls designed to give higher bounce to enable players to practice back foot shots at reduced ball speeds.Players can play hooks and pulls safe in the knowledge that the softer ball will not cause injury.Also used for junior age groups to provide bounce when the BOLA is on it's shorter legs.