Marathon offers U.S.-origin imported sensors, with both of its acquired brands featuring diameters of 22/25mm, providing a variety of options. Marathon features a unique electrode structure, with the electrode design ensuring the probe's stability and durability. The protective tube is made of RA330 alloy, a material known for its red hardness and corrosion resistance, enabling stable operation at high temperatures.

The working principle primarily utilizes the electrical conductivity of zirconia to measure the oxygen concentration in gases. Marathon models typically start with "F" or "MMI", offering a complete range. They are heat-resistant but fragile. Available lengths include 600, 800, 1000, 1200, and 2000, with a diameter specification of 25mm.