Natural Path / Silver Wings’ colloidal silver is guaranteed to be colloid (1-10 Nanometers) with the highest percent of the silver particles at 2 Nanometers. Tested for purity, particle size and concentration (150PPM) by in-house and qualified third-party independent laboratories. <br/> <br/> <b> SUGGESTED USE: </b> 4 sprays, 1-3 times daily in mouth and swallow as needed for immune support for up to 10 days.* For extended use, please consult your healthcare practitioner. <br/> <b> STORAGE: </b> Keep Colloidal Silver in a cool, dark place, never on a sunny window ledge or in the refrigerator or freezer. For long-term storage, colloidal silver should be contained in a dark, amber colored glass. There is an inherent electric charge in all plastic that causes the silver to collect on the inside of the plastic container. It should not be stored for prolonged periods of time in plastic. <br/>