HEPA Filters made by our filter materials, cartridges, activated carbon, photo-catalyst, cold catalyst, nano-silver, functions well on absorb and purify the airs of ammonia, fluorine, formaldehyde, methanthiol, hydrogen sulfide etc. Also, its super strong on sterilizations, ordinary bacteria, stubborn bacteria and fungus killings. Performance: Broad spectrum activity: absorb and bactericidal effects. Long-acting properties: nano silver fiber is water-washable, and durable, Safty: non-toxic, harmless, anti-allergic, Application: water treatment and purification, air HEPA filters, air filter bags etc. Clinical nano silver masks, exposure suits, and hygiene healthcare products.