Does what it says on the...bag! I like the colour white because you can see where it starts to be saturated with cat's urine and remove and freshen up litter. It dries the fecal matter without leaving a pugent scent. I find it ideal to use these cat litter crystals with an electric cat litter box, where the machine can remove the lumps to a covered box without you having to clear it everyday and does not leave nasty smells lingering because of the drying properties of the crystals. For this price, you get 4X 5L bags, i find this an excellent deal and i certainly will continue to be a customer.