Ultra Cat Health Monthly Monitor Crystal, 16oz Cat Litter Additive that helps cat owners monitor their cat's health. Detects many urine abnormalities; often before the cat exhibits external signs of illness. Works with all types of cat litters. Cat Litter Additive that helps cat owners monitor their cat's health Detects many urine abnormalities; often before the cat exhibits external signs of illness Works with all types of cat litters Cat Litter Additive that helps cat owners monitor their cat's health Detects many urine abnormalities; often before the cat exhibits external signs of illness