Water thief is characterized by which feature?

• A. A device with a 2½-inch inlet and 2½-inch outlet plus two 1½-inch outlets
• B. A device to connect into hydrant
• C. A device to measure flow
• D. A device to connect two hoses in parallel

Answer: (C)

A water thief is defined by what it does: it’s used to measure the flow of water from a hydrant or supply line. In firefighting practice, you want to know how much water is actually available so you can pump effectively and plan your attack. The water thief provides a way to gauge flow, often by incorporating a measurement method or by being used in conjunction with a flow meter or gauge during hydrant testing or supply setup.

The other descriptions describe physical configurations or connections (inlet/outlet sizes, connecting into a hydrant, or feeding multiple hoses in parallel). Those are about how a device might be built or connected, but they don’t capture the defining purpose of a water thief, which is to measure flow.