Smoke Hunter 2.0 Personal Air Purifier with Replaceable Filter Element Suitable for Travel and IndoorThe mouthpiece of this personal air filter features a duck beak design inspired by a baby's pacifier to prevents from leaking 100%! The service life of each filter element is at least about 1000 puffs, because the gas is granular, long term use of the filter element will certainly cause the accumulation of gas particles, which is a physical common sense, when you feel clogged or poor performance, you can buy the replacement of the filter element, very