seconds with the waterproof Nutra-Wand-pH Truncheon. Auto-on Truncheon has a pH scale from 2.1- 10.8 and features an easy-to-read illuminated display, one-touch calibration, long-lasting replaceable probe, and Automatic Temperature Compensation (ATC). Reliable Truncheon comes with detailed instructions and a manufacturer's guarantee - three year on meter, one year on probe. I am the manufacturer of the YM Instrument Co,.Ltd. in China. With it's easy to read illuminated display, one-touch calibration system, super clear instructions and no buttons to push, measuring pH just got a whole lot simpler. The flashing lights you love so much; the easiest calibration system ever; reliability only YM products can provide; the longest lasting replaceable probe on the market; auto-on and off just like the Nutra-Wand EC Truncheon; Automatic Temperature Compensation; a scale of 2.0 pH through 10.9 pH and it's available worldwide. Suitable for hydroponics, aquatics, pool and spa, waste water treatment, horticultural and agriculture, wherever an accurate measurement of liquid pH is required.