This is the original Sweet PDZ product that was introduced in 1983. The key advantage of this small particle size is the fact that a person can more thoroughly and comprehensively cover the wet spot or problem area. This results in a faster acting performance of absorbing and adsorbing the ammonia and odor. Many Sweet PDZ users translate this faster performance to better performance, and will swear that the Sweet PDZ Classic/Powder outperforms Granular. Who are we to argue with our customers? An additional benefit to some users, is the fact that the Powder usually has a lower retail price. As much as $1.00 less per bag versus Granular Sweet PDZ.