This is the Infrared Temperature Gauge with Stopwatch from TrakPower. FEATURES: Displays temperatures in Fahrenheit or Celsius Temperature range of -27 to 428°F (-33 to 220°C) Stopwatch counts lap times to the nearest 0.01 second One second response time Backlit LCD screen One year limited warranty beginning at date of purchase INCLUDES: Infrared Temperature Gauge with Stopwatch, Nylon Carrying Case and Lithium Battery SPECS: Display Type: Custom backlit LCD Display Resolution: 0.1°F or C Temperature Range: -27 to 428°F (-33 to 220°C) Ambient Temperature Range: +14 to +122°F (-10 to +50°C) Response Time: 1 second Infrared Accuracy: 4°F (2°C) or +/- 2% of reading, whichever is greater Field of View Label: 1:1 optics ratio Emissivity: Adjustable from 0.05 to 1.00 (1.00 default) Battery Life: 960 (15 second) readings, or 1 hour continuous Battery Type: Replaceable CR2032 lithium (included) Dimensions: 3.4 x 1.9 x 0.9" (85 x 48 x 23mm) Weight: 1.53oz (43.6g) COMMENTS: This gauge accurately measures R/C engine temperatures, but modeler should always refer to engine instruction manual for proper tuning and set-up. Temperature alone is not an accurate indicator of proper engine performance. jxs 07/18/11 ir/jxs