FILTER, BACTERIA (50/CS) CARFUS AirLifeâ„¢ disposable respiratory bacteria filters trap bacteria and viral particles by electrostatic attraction and their dense makeup Filters provide defense against infection Small, lightweight and translucent, our hydrophobic filters resist moisture and offer easy visualization of water buildup with 22mm 7/8 inch O.D. adapters and 6 inch flextube Bacterial filtration efficiency (BFE) 99.9 percent Viral filtration efficiency (VFE) 99.7 percent