TONOR Portable Formaldehyde Detector with Sound-Light Alarm White MULTIFUNCTIONAL FORMALDEHYDE DETECTOR: LCD display show formaldehyde concentration 0-5PPM, current temperature -15 to 50 degrees Celsius DAILY NECESSITY: Indoor toxic gases detector, necessary for a new house or office, Formaldehyde is harmful for peoples health, especially affects pregnant women, kids and old people, help you detect whether you are in a healthy environment SOUND, LIGHT and VIBRATION ALARM: high / low concentration alarm, sound, light, vibration, three level alarm modes, give you all-round protection SWITCHABLE F/C MEASUREMENT UNITS: Temperature units F / C options, give you convenient operation SIMPLE OPERATION, PORTABLE and DURABLE: 5 operate keys, you will know how to operate it upon power it, (note the battery is not included), and you can put it in your bag or pocket wherever and whenever needed