' Digital Hydronic Manometer, Pressure Range +/-300 psi, +/-2068 KPA, Pressure Resolution 0.001 psi, 0.01 KPA, Pressure Accuracy +/-1 Percent of rdg, Operating Temp. Range 40 Degrees to 113 Degrees F, 4 Degrees to 45 Degrees C, Flow Range (GPM) 0 to 9999, Max. Pressure (PSI) 300 PSI, 2068 KPA, Fluid Temp. Range (Deg. C) 32 To 212F, 0 To 100C, LCD Display, Memory 1000 Reading, Power Source 4 AA Cell Batteries, Battery Life Minimum 12 Hours '