Diamond Billiard Products 2 1/4" Tournament Cue Ball not only does it meet all the professional standards for density, balance, diameter, roundness, color, gloss, hardness, and weight, but it is also designed for exceptional durability. Made with an ultra-hardened vitrified surface and ultra-high density, it boasts unparalleled scratch and impact resistance. While specifically optimized for use in Smart tables, this cue ball can also be used with any 2 1/4" ball sets.