A Specific Gravity Bottle with a Thermometer is a type of laboratory equipment used for determining the density of liquids. It consists of a cylindrical glass or plastic bottle with a narrow neck and a built-in thermometer. The bottle is filled with a liquid, and its weight is measured to determine its specific gravity, which is a measure of its density relative to water.

The thermometer in the bottle allows the user to accurately measure the temperature of the liquid, which is required to calculate its specific gravity, as density is temperature dependent.

Specific gravity bottles with thermometers are commonly used in the chemical, food, and pharmaceutical industries to determine the quality and purity of liquids.