Impact-resistant Gasman personal gas monitor weighs less than 5 oz. When a hazardous gas is detected, unit alerts user by vibrating, sounding a 95-dB. alarm and flashing bright red/blue light. Fits into pocket or clips onto belt. Features single-button control and interchangeable module, which allows monitoring of oxygen and toxic and flammable gases. LCD screen allows clear view of all readings, alarm conditions, and battery life. Unit comes with data and event logging. A built-in warning lets user know when calibration is due within 30 days. Choose from 2 models.