Powerful, Effective and Natural;500 PPM - 4 oz;Silver was commonly used in past centuries for antimicrobial purposes. Various forms of silver are used today for the same reason. Ultra Silver is safe and non-toxic when used as directed. There are no known drug interactions of any kind. Ultra Silver is a non-prescription dietary supplement providing silver in a safe and bioavailable form. Ultra Silver is made without the use of electrolysis and contains no nitrates or salts. For lower concentrations, Ultra Silver may be further diluted with pure water. In this manner, Ultra Silver provides you with a premium product at the best possible value.