JBB single piece spare solid pool ball 3 number, very strong & scratch resistant withstands over 50 times more impacts and is far more scratch resistant than other balls. No flat spots on the ball, Optimal rebound The unique elasticity of the phenolic resin is calibrated for optimal rebound which allows a perfect control of every shot. The ultimate in balance The perfect homogeneity of the material in plain balls as well as in numbered balls perfectly true and accurate roll.