Senva TGW-ACN-AS : Wall Carbon Monoxide/Nitrogen Dioxide Sensor/Controller, 5% Accuracy, CO : 0-200ppm (Default); 0-1000ppm (Menu Selectable), NO2 : 0-10ppm (Default); 0-30ppm (Menu Selectable), 4-20mA/0-5VDC/0-10VDC Output, LCD Display, Opaque ABS/Polycarbonate Enclosure, 7-Year Limited Warranty, Made in USA