Testo 300LL Longlife Flue Gas Analyser with NOx – Smart, Efficient, & Reliable Flue Gas Analysis This Winter we are offering a FREE Premium Magnetic Work Light  with any testo 310 (2nd gen) Flue Gas Analyser Kit. The Testo 300LL Longlife Flue Gas Analyser with NOx sensor is a state-of-the-art tool designed for the installation, commissioning, and maintenance of commercial heating systems. This advanced analyser comes equipped with high-performance O2, CO (H2-compensated), and NO sensors, allowing for precise measurement of up to 30,000 ppm. Ideal for long-term use, the Longlife sensors boast up to 6 years of service life, e