KAMUI Chalk contains a much finer particle size than standard chalk.The purpose of this is to maximize the friction and offer a larger sweet spot to generate more spin to the cue ball. KAMUI Chalk also Reduces slippage and decreases deflection,giving the player a more accurate aim when english is applied. The RED .98 is for Extreme shooting: Giving the player the best possible friction while maximizing the sweet spot on the cue ball. More adhesion allows the chalk to stay on the cue tip longer. The BLUE 1.21 is for more consistent playability: Improved longevity, with a harder compound, to give the player more confidence with a Pre-Shot routine. Reduces compound transfer to the cue ball. THESE ARE SOLD PER CUBE.