The good quality type worn by medical personnel. Thanks. 

They're saying these don't really work with Omicron.

large pharmacy.

I have got my on ebay from china at the beginning of covid. $2.

The problem is, at cold environment, like going from the street to hospital, bank, where air con is on full blast, within 20 seconds you can't see through moisture on glass. Need to cool down skin and body before putting them on