Enerac 500-5 Combustion Analyzer is designed to help you meet the challenges of a rapidly changing regulatory environment. It is flexible and easy to use. Enerac 500-5 measures NO-CO-O2, Draft and Temperature. It includes Printer. Equally at home with a simple combustion test, or with the monitoring of more sophisticated emissions reduction systems, the Enerac 500-5 is designed to provide years of trouble-free service. It is flexible enough to be tailored to meet your specific needs yet simple enough to be completely maintained in the field. Enerac 500-5 Combustion Analyzer is housed in an aluminum case that is rugged yet light-weight. Some of the customers have been using their Enerac analyzer for 20 years or more! Enerac 500-5 comes equipped with NiMH rechargeable cells for day-to-day operation, but can also be powered from standard AA-size. The AC adapter charges the battery and can power the unit continuously. All of the Enerac combustion and emission analyzers are made in the USA. Free ground shipping within continental US.