Firstly，we can see the difference is that M2000 can monitor the gases CO2, but LKC1000S+ can not. I have listed the difference in the following picture. I believe that you will find out the best model to meet your requirement.

Firstly，we can see the difference is that M2000 can monitor the gases CO2, but LKC1000S+ can not. I have listed the difference in the following picture. I believe that you will find out the best model to meet your requirement.

  Aerosol refers to a suspension system that consists of fine solid particles or liquid droplets in a gas medium. It can be natural or anthropogenic. Natural aerosols are fog, mist, dust, forest exudates, etc., while anthropogenic aerosols are particulate air pollutants, smoke from fuel combustion and unburned fuel in furnaces, engines that used in heavy industries and vehicles.   The solid or liquid particles have diameters generally between 0.001 and 1000 um. From the perspective of fluid mechanics, aerosols...

  Aerosol refers to a suspension system that consists of fine solid particles or liquid droplets in a gas medium. It can be natural or anthropogenic. Natural aerosols are fog, mist, dust, forest exudates, etc., while anthropogenic aerosols are particulate air pollutants, smoke from fuel combustion and unburned fuel in furnaces, engines that used in heavy industries and vehicles.   The solid or liquid particles have diameters generally between 0.001 and 1000 um. From the perspective of fluid mechanics, aerosols...

Also known as HCHO, formaldehyde is a chemical that compounds hydrogen, oxygen, and carbon. It can be found in all living things. This chemical can be irritant in skin, eyes, nose and throat. However, it is an extensive regulated material, governments regulations implement standards to protect human health and the environment. This chemical is used to a wide range of valued- added products. Formaldehyde also occurs naturally in the environment. It is produced in small amounts by most living organisms...

Also known as HCHO, formaldehyde is a chemical that compounds hydrogen, oxygen, and carbon. It can be found in all living things. This chemical can be irritant in skin, eyes, nose and throat. However, it is an extensive regulated material, governments regulations implement standards to protect human health and the environment. This chemical is used to a wide range of valued- added products. Formaldehyde also occurs naturally in the environment. It is produced in small amounts by most living organisms...