•Rugged design with automatic temperature compensation. •Simultaneous display of oxygen and temperature readings. •Waterproof housing. •Portable and convenient. •Probe performance indicators ensures optimal probe condition. •Meter kits include cleaning solution, electrolyte solution, polishing foil and 3 replacement DO membranes. •Model 3210 has automatic barometric pressure compensation, automatic salinity compensation, GLP functions and can be calibrated to Winkler. •Model 3210 also has 200 manual data point storage capacity. •Power: 4 AA batteries. •Warranty: 3 years.