Gas Detection Instruments from TPI. A full range of TPI Gas Detection instruments for all of your job needs, including Combustion Analyzers, Carbon Monoxide Analyzers and Detectors, Combustible Gas Leak Detectors and Refrigerant Leak Detectors. A771 Carbon Monoxide Adapter for DMMs and Clamp Meters 706 High Carbon Monoxide Analyzer 707 Carbon Monoxide Analyzer 770 Carbon Monoxide Monitor 777 Personal CO Monitor 719 Combustible Gas Leak Detector 720b Combustible Gas Leak Detector 721 Combustible Gas Leak Detector 725a Pocket Combustible Gas Detector 725L Combustible Gas Leak Detector 735A Combustible Gas Leak Detector 775 Carbon Monoxide & Combustible Gas Leak Detector HXG-2D Combustible Gas Leak Detector HXG-3 Combustible Gas Leak Detector 750a Refrigerant Leak Detector 753a Refrigerant Leak Detector SP700 Carbon Monoxide Meter SP1000 IAQ Ambient Air Direct CO2 Meter