The TTO Digital Temperature Gauge allows you to easily monitor your engine's temperature -40°-300°C/575°F ensuring you that your engine is not over heating. Trail Tech's TTO Temperature Gauge offers features that include an easy to read LCD display, and an ultra-thin design. The LCD display lets you to easily view all gauge readings regardless of the angle or lighting conditions. Select the proper size of temperature gauge/meter off of the list of available colors from the drop down menu above. Options for TTO Surface Mount Gauge: Color: Black Sensor Style Coolant Hose - Includes aluminum fitting to splice into a coolant hose. For hose sizes 16mm, 19mm, 22mm, and 25mm. Radiator Fin - Small sensor that installs between your radiator fins. Available in 7mm, 8mm, and 10mm lengths. Spark Plug - For recording cylinder temperatures, this sensor is a small ring that attaches to the spark plug. Available for 10mm, 12mm, and 14mm spark plug thread sizes. Temperature Probe - This is a threaded sensor meant for use on specific parts like thermostats and other components with threaded holes. Available in M6x1.0 and 1/8x28 BSPP.