Description: Food Grade SDF Series _Precipitated silicaDalian Dalian Fuchang Chemical Co., Ltd is a professional silicon dioxide manufacturer. mainly products including fumed silica, precipitated silica, silica matting agent.
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
The 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.