Description: #Hearing Product • Raw Ranked SitesThe operational key for this scheme was in Harvard, where "one of the researchers was the chairman of Harvard's Public Health Nutrition Department — and an ad hoc member of SRF's board." (Source) Their review was published in a 1967 issue of the New England Journal of Medicine.
Type: Disposable / Reusable
Function: Coronavirus, Anti-pollution, PM2.5, cold, dust, pollen, allergy
Package: 10pcs/20pcs/50pcs per pack
Certification: CE, FDA, ISO
Min Order: 1000 Pieces