The REOTEMP S2-F1 Pipe Clamp Surface Hot Water Thermometer is a quality thermometer for use on pipes, boilers lines, process lines, or hot water pipes where a clamp attached thermometer is needed. The thermometer offers an approximate reading of the temperature inside the pipe by sensing the temperature on the pipe surface. Please note some heat loss will occur as the temperature conducts trough the material of the pipe and thermometer. The thermometer accuracy is rated at +/- 2.5-2-2.5%. The S2-F1 features a glass lens that will not yellow over time and an easy-to-read 2.5" dial. The temperature range is 32 to 250 Fahrenheit. This unit comes with a 1-year limited warranty.