Precison ASTM plain form hydrometers made to meet ASTM and API specifications, which do not incorporate a thermometer in the hydrometer

The temperature standardization is 60/60F. The hydrometer scale division are 0.1 degrees.

Tall form, 330mm, have 12 degree ranges; Short form, 163mm, have 6 degree ranges.

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