AlphasenseyeB4The fourth electrode of the series electrochemical sensors as a auxiliary electrode, used to compensate zero point current, making it have a high signal level, low zero point current characteristics, resolution can be low to less than10 ppb, response rapid, response time short, anti-interference, wide range of work and other obvious advantages, can be used for fixed and portable equipment, urban areas/Lɔ̈ɔ̈i de ɣän kɔ̈k yiic ku jɔl ya gas ye cɔl smoke analysis.