A bait and switch.
Trash. Site claims 2 filters will be sent. I verified this with them. Got a torn bag with one filter removed. Added to that the price is for 2 filters. The box was not sealed properly leading to the filter being exposed to dirt,liquid,and undoubtedly the virus at some point. The filter is worthless as the seal on it was broken. These people, if they are trully in this field should know that this filter is worthless. They do not answer any email unless it deals with buying something... beyond that you will he stuck in a phone system that will tell you someone will call you in 10 minutes ,no one does. Its not worth the problems and there is no value here.