1ORP Electrode: It is harmless to the human body and has good conductivity, and widely used in the test of aqueous solutions. 2Wide Use: For most ORP meters and controllers with BNC Q9 connectors, used in water source systems such as aquariums, hydroponics, swimming pools. 3PH Test: Measure the pH value in the aqueous solution for accurate up and down adjustment, which needs to be used in conjunction with the meter. 4Strong Conductivity: The ORP replacement probe is made of sturdy and durable materials, has good conductivity, and is environmentally friendly. 5ORP Probe: Different water quality ORP ion oxidation degree is always can help remove harmful substances in the water you use to. Item Type: ORP Replacement Probe Material: Plastic Electrode Length: Approx. 155mm / 6.1in (Delivered with liquid) Probe Type: Sensitive Crystal Ball Bubble Range: 0~1999mV Accuracy: 5mV Applicable Temperature Range: 5~70 Electrode Potential: 245-270mv (15~30) Internal Resistance of Reference Electrode: 10k Electrode Stability: 8mv/24 Electrode Indicator Electrode: Good Conductivity Electrode Plug Type: Q9 PH Electrode Wire Length: Approx. 1.2m / 3.93ft Gross Weight: Approx. 89g / 3.14oz Can be widely used in water source systems such as aquariums, hydroponics, hot springs, swimming pools, etc. 1 x Electrode