These Exhalation and In-line filters feature a hydrophobic filter medium. The Exhalation version is typically used with Mercury Medical self-inflating BVMs, while the In-Line version is used with Flow-Safe CPAP devices along with other appropriate medical devices. These filters have been independently tested and provide a BFE of 99.96% on particles with an approximate size of 3.1 microns, and VFE of 99.81% on particles with an approximate size of 3.3 microns.