Online Conductivity / EC Meter ORP-139M is made of high-quality ABS material, and the surface layer is coated with the anti-static layer. The anti-static ability is higher than that of an ordinary ORP controller, a+nd it is durable and durable. The live digital display shows the ORP value and the backlit display makes the observations clearer. SMT placement technology; ergonomic design with adapters and boxes for easier carrying. It can be continuously measured for 24 hours to avoid reading errors caused by low battery. Equipped with a BNC composite electrode for easy electrode replacement.