Check the listing for details. Fieldpiece Cat45 Combustion Analyzer With Case and Accessories. Condition: Used. Listed at 1100.00 USD. The Fieldpiece Cat45 Combustion Analyzer is a portable gas analyzer designed for analyzing gas emissions in various industrial and commercial settings. This unit from Fieldpiece comes with a convenient case for easy storage and transportation, along with accessories to enhance its functionality. Perfect for testing and measurement applications, this combustion analyzer is a reliable tool for ensuring optimal gas performance and safety in gas systems.