Have the KN95 respirators being sold by Wyze been tested? Who is the manufacturer?
Here is the CDC web-page (updated 5/8/20) that shows mask/respirator test results for several manufactures. Even though this is a material only test, some tested very poorly.
An important quote from the CDC page:
Most of these products have an ear loop design. NIOSH-approved N95s typically have head bands. Furthermore, limited assessment of ear loop designs, indicate difficulty achieving a proper fit. While filter efficiency shows how well the filter media performs, users must ensure a proper fit is achieved.