Horizontal drum Cast-iron Fill Gauge allows you to easily check liquid level of a horizontal drum at a glance – no surprise re-orders or stock depletions. Use indoors or out. Sight gauge shows how much liquid remains in a 30 or 55-gallon (110L-200L) drum. drum gauge installs easily by threading into a standard ¾" NPT bung hole and accepts any ¾" faucet. Rugged zinc-plated, cast-iron body stands up to heavy use. Heavy gauge glass tubing is protected with a chrome-plated housing and permits use w