Function --Filtered air will be ionized at a rate of 0.3L/min --Negative ionized air emitted then sediments tiny and harmful particles in the the air --It can be used to sleeping rooms, study rooms and office Specification --Power: DC 5V +/- 5%, through USB Port --Weight: 90g approx. --Working Environment: -20 ~ 50 癈 ( 4 ~ 122 癋) --R.H.: 80% --Working Space: 8 - 27 cube meter --Negative Ionizer: approx. 15000/cc at 0.3m from unit, approx. 4000/cc at 2m from unit