Base Model Description Long Life O2 sensor (with 3 - 4 years life expectation): 0 - 21% CO (H2 compensated) sensor: 0 - 10,000 ppm (short interval reading overload 20,000 ppm) Calculated CO2 or optional NDIR measured CO2 (OPTION 64618 or 65648) Large fuel type list + user definable fuel types Differential Temperature Measurement Differential Pressure Measurement and Draft Measurement Modern, slim line enclosure with fixing magnets Dirt resistant - illuminated key pad Super bright, color 4.0” TFT display with LED backlight (customizable and zoom function) CO protection using 2nd pump (protects the CO sensor against unwanted high CO concentrations) High energy Li-lon battery (for up 20 hours operation time) For More Information Visit Here: https://www.viasensor.info/products/temperature-probe-100mm-ss-tip-1