Precison API combined form hydrometers made to meet API specifications, which incorporate a thermometer in the hydrometer

The temperature standardization is 60/60F. The hydrometers will perform with the same accuracy as the ASTM hydrometers with mercury thermometers.

The thermometer is made with a non-mercury, blue spirit, has a range of 20 to 120 degrees farenheit.

Used to measure the density according to API degree scale for petroleum applications.