The TGS 2603 has high sensitivity to low concentrations of odorous gases such as amine-series and sulfurous odors generated from waste materials or spoiled foods such as fish.
The TGS2620 has high sensitivity to the vapors of organic solvents as well as other volatile vapors. It also has sensitivity to a variety of combustible gases such as carbon monoxide, making it a good general purpose sensor.
The TGS3830 is a semiconductor sensor with a high sensitivity to R-134a, the most promising alternative to R-12, commonly used in air conditioning systems and refrigerators.