... ,newest calendar desigen:display year, moth, day, time, week;2,the air tester is test VOC, dust bacteria, stink,weat, etc;3 ... red will alarm, remind users that air has reached the level of pollution, suggesting users open the window to take a breath or ... bacteria, dust, stink, sweat, etc. VOC is test the organic volatic gas in the air, mainly tolunene, xylene etc(home decoration,volatile gas ...