Monitor your cat’s health from home with Fresh Step Crystals Health Monitoring Cat Litter. The innovative Fresh Step crystal cat litter contains pH-activated crystals that change colors when they help detect irregularities in cat urine, helping to catch illness early. Designed to be a proactive partner in your cat’s health, the unscented cat litter crystals indicate issues such as UTIs, bladder stones and acidosis. A color scale on the package makes it easy to find out what the colors mean. Ammonia Block technology in this Fresh Step cat litter helps control odors for up to 30 days, keeping the kitty litter box clean and your cat happy (1). A lightweight cat litter formula makes the litter easy to use and gentle on your cat’s paws. Cats are a mystery, but their health shouldn’t be. Trust Fresh Step Cat Litter Crystals to easily monitor your cat’s health and detect potential illness early. (1) See package for more information on terms and conditions