The Grainger website features liquid level gauges for drums and tanks. These gauges allow you to visually monitor liquid levels in your drums or tanks. They feature either galvanized steel or HDPE float materials that rise and fall with the liquid level. Key features include compatibility with various liquids like water, chemicals, petroleum products, etc, ability to withstand temperatures from -40 to 200°F, floats from 1.5" to 48" long, and assemblies from 36" to 240" long. They can be mounted vertically or horizontally through a tank top or side bung. Overall, these are durable, versatile liquid level gauges to help monitor your drum or tank contents.