Lutron ORP-203
ORP Meter

Specifications:

• Display: 13 mm ( 0.5″ ) LCD, 3 1/2 digits.
• Range: 0 to 2000 mV.
• Resolution: 1 mV.
• Accuracy: ± (0.8 % + 1 d) – 23± 5 ?.
• Input impedance: 1000 Meg ohms
• Sampling Time: Approx. 0.4 second.
• Operating Temperature: 0 to 50 ? ( 32 to 122 ? ).
• Operating Humidity: Less than 80 % RH.
• Power Supply: DC 9V battery. 006P, MN1604 ( PP3 ) or equivalent.
• Power Consumption: Approx. DC 2.0 mA.