The 20-600 is a portable binary gas analyzer designed to measure binary gas mixtures. It is ideal to be used in identifying NH3 in Air, H2 in CH4, Freon in Air, Refrigerant 12 in Air, CO2 in N2 (flue gas), Natural Gas in Air and many others. This device has dual range calibration and has a response time of less than 30 seconds. It has two power sources; an Ac or an rechargeable battery. It calibrates as low as 0.5% CO2 in air.