Innovations in Water Monitoring Optical RDO® PRO-X Dissolved Oxygen Probe The In-Situ® Rugged Dissolved Oxygen (RDO) PRO-X Probe uses optical technology for measuring dissolved oxygen (DO) in demanding process environments. The U.S. Environmental Protection Agency (EPA) has approved In-Situ RDO methods for use in Clean Water Act programs. NPDES permit holders can use the RDO PRO-X Probe and Con TROLL® PRO System for monitoring influent, effluent, and treatment processes. Visit the In-Situ website for details and start using breakthrough technology. Robust Construction • • • Accurate Results • • Simple Design • • • Automates setup and reduces user error—Calibration coefficients and expiration clock are loaded into sensor cap. Eliminates membranes and filling solutions Flexible communications—Standard 4-20 mA, Modbus/ RS485, and SDI-12 outputs Cost Effective • • • Runs aerators efficiently and mitigates risks Eliminates the need for a costly transmitter or controller, and requires only 8 to 36 VDC power Includes complete instrument with a standard 10-m cable Resists abrasion and photobleaching effects Withstands high salinity environments—Inert, non-corrosive materials used to construct probe body and sensor Insensitive to interferences that plague membrane-based sensors (hydrogen sulfide, chloride, ammonium, and others) Includes diagnostic tools to help you evaluate sensor health Provides ±0.1 mg/L accuracy from 0 to 8 mg/L; ±0.2 mg/L accuracy from 8 to 20 mg/L; and ±10% of reading from 20 to 50 mg/L Operates with very low drift for long periods of time Responds quickly to oxygen and temperature changes Delivers consistent, reproducible results (<0.05 mg/L) Municipal/industrial water and wastewater treatment Food/beverage process control Aquaculture settings Dam discharge monitoring

Optical RDO® PRO-X Dissolved Oxygen Probe Key Advantages • RDO PRO-X Oxygen Probe Sensor type Optical DO probe uses RDO-X Sensor Cap Range, DO 0 to 50 mg/L Accuracy, DO ±0.1 mg/L, 0 to 8 mg/L; ±0.2 mg/L, 8 to 20 mg/L; ±10% of reading, 20 to 50 mg/L Resolution, DO 0.01 mg/L Response time, cap T90: <45 sec. T95: <60 sec. @ 25° C Range, temp. 0° to 50° C (32° to 122° F) Accuracy, temp. ±0.1° C typical Resolution, temp. 0.01° C Salinity comp. Fixed or real-time capable Barometric comp. Fixed or real-time capable Methods EPA-approved In-Situ® RDO methods 1002-8-2009, 1003-8-2009, 1004-8-2009 Standard...