Less toxic than table salt.... Odourless & Non staining.... Safe for All Cage Animals.... Rx eradicates pests physically, not chemically.... The uniquely sized particles pass through the exoskeleton blocking the stomach tract and simply dehydrates. The pest can not build an immunity to the product therefore it works long term.... Due to the Milling process, Rx becomes negatively charged which keeps the product in the environment long term for continued effectiveness