The HI76407 is a standard Clark-type polarographic dissolved oxygen probe for Hanna’s benchtop and portable dissolved oxygen meters. The probe is constructed of durable ABS plastic and contains an integrated temperature sensor for temperature compensated measurements. It is compatible with our HI76407A/P PTFE membrane caps. Each membrane separates the probe’s platinum cathode and silver anode from the water sample being measured. Oxygen diffuses across the membrane and interacts with the polarographic system to produce a current proportional to oxygen concentration. Each cap is easily filled with HI7041 electrolyte and screwed onto the probe. The probe’s tapered design makes it ideal for BOD measurements.