Features: • Measures Oxidation Reduction (REDOX) Potential • One Scale: mV • Digital Calibration (push button) to any point within the meter's range • Low battery warning • Professional model • Waterproof body - it floats! • Auto-off function/data-hold function • Highly versatile - 0.5 and 0.7 scale • Large and easy-to-read LCD screen • Replaceable sensor (model SP-02) • Includes a cap, batteries, and lanyard