Thanks PC2K!! Yes, it is a spec.. I believe the 95 is 95% of 0.3micron filtration... I guess looking at most sites, the 9210 is touted as being effective against airborne virus' (SARs, Bird Flu, etc), whereas the 9211 has no mention of that "feature". Due to the recent heat wave in Southern California, I think the 9211 would be a better choice, but just want to make sure it covers the "airborne virus'" as well.. <img src="/images/graemlins/smile.gif" alt="" />

Oh, yeah, after more researching I discovered that contraption on the 9211 assists in hot and humid conditions as Glock-a-roo mentioned.