A permanent guard against microbes that cause odor Sliver is a natur al Antimicrobial, it is non-toxic and hypoallergenic SmartSilver antimicrobial is an EPA-registard, Oeko-Tex approved, nanosacale silver additive When SmartSilver nanoparticles come in contact with moisture, they release low levels of silver ions that prevent the growth of micorbes that cause odor and material degardation SmartSilver is made in the USA