Clip-on Pipe Thermometers complete with fixing spring, 0 + 120°C&F 66mm Steel Case & Polished Bezel. ideal for fixing to your engines coolant pipes either entering or exiting your engine, with the use of two you can get an accurate idea of both the inlet and outlet temp at any one time just by glancing at the gauge. Comes complete with fixing spring which adjusts for a wide range of pipe diameters