That's a neat trick I wonder how they do it?

Their specs say
Particle Retention (microns)
.1 nominal
.4 absolute

Norovirus the food/water born virus that keeps hitting the cruise lines is
27-35 nm

The math just isn't adding up
.1 microns is 0.0000001m
35 nm is 0.000000035m

If you guys know how it works let me know because I have some serious doubts as to it removing viruses...