GPI Digital Flowmeter 3 GPM Measures liquid flow rates from .3-3 GPM. Commercial grade turbine design. Corrosion resistant body. 1" female pipe thread fittings for easy connections. Operating temperature range: -40 to +250 degrees F. Installs vertically or horizontally. 2 lithium batteries, included. Manufactured by GPI, the leader in fluid technology. We recommend installing your flowmeter on Quick Disconnects for easy storage & security, and the Plastic Flowmeter Cover to protect your meter.