Our model VE7 heated FID is being manufactured since 1974 and is the first heated THC analyzer ever built with a permanent back purge sample filter. It is still the most liked heated FID throughout the stack testing community due to its legendary ruggedness, forgivingness and long standing accuracy and sensitivity. The VE7 belongs to the very first total hydrocarbon analyzers being officially certified for compliance in Europe. In the USA, a significant part of the Method 25A was written around the VE7.