Global Water Instrumentation offers dissoved oxygen instruments, such as sensors (water oxygen level measuring devices), industrial transmitters, optical sensors (for measuring dissolved oxygen concentrations in liquids), meters, probe kits, portable meters and handheld meters.

The Sensorex line of dissolved oxygen probes are galvanic sensors with large reservoirs of electrolyte. They are available with mV or 4-20mA outputs. Their Lab dissolved oxygen probes are designed for use with galvanic dissolved oxygen meters, transmitters and controllers. Their Process dissolved oxygen probes feature a large volume electrolyte reservoir for long term continuous deployments.

Honeywell offers a line of analyzers, transmitters and dissolved oxygen probes. Products include DierectLine ppm and ppb transmitters, DirectLine Equilibrium dissolved oxygen probes, and a multiple input analyzer for measurement of pH, ORP, conductivity and dissolved oxygen.