>EASY TO USE: Filter Odor and Smoke Upon Exhale. Allows you to reduce second hand smoke for roommates, family and neighbours. >HIGH QUALITY MATERIALS: Aircraft Grade Aluminum Casing and 2 Stage Medical Grade Filter. Activated Carbon Filter + HEPA Filter >REPLACEABLE CARTRIDGES: Instead of Buying a Whole New Filter, Simply Replace With a Cheap, Easy To Change Replacement Filter! Also Has Removable Mouthpiece and Cover for Easy Cleaning >LONG LASTING: Lasts Up to 500 Exhales Before Needing to Be Replaced. The Average User will use this for 2-3 months before needing to replace.