ISCO 4230, Bubbler Flow MeterCondition:* Used, Demonstration Unit. Unable To Test. As Pictured.Additional Notes:* The 4230 uses the bubbler method of level measurement.* Theflow meter is normally used with some type of primary measuring device to measure flow in an open channel.* The 4230 has built-in standard level-to-flow conversions, that cover the vast majority of open channel flow measurement situations.Teledyne ISCO4230