The ENVI-Stack from Environics is the latest evolution in continuous emission monitoring (CEM) systems that offer turn-key, stack to analyzer solutions, based on IMS and GC-IMS technology. Ion Mobility Spectrometry (IMS) is a simplified atmospheric pressure time-of-flight technique that is highly selective with low ppb to ppm sensitivity and can operate in the most severe conditions. ENVI-Stack does not require the use of paper tape, pre-concentrators or chemical reagents.