YSI EcoSense pH100A [606075] pH / ORP Meter (Instrument only). The YSI pH100A EcoSense pH100A pH/ORP Meter provides the most accurate data in the most affordable format. The instruments feature an easy-to-use interface, one-hand operation, IP67 waterproof case, and low cost of ownership over the life of the product. The pH100A is designed for quick, accurate results in an economical platform. The ability to measure pH, mV/ORP, and temperature in a simple, compact handheld allows the instrument to be used in multiple applications. With a one-year instrument warranty, six-month electrode warranty, calibration backup, and a variety of cable/sensor options (glass bulb, flat tipped, and piercing tipped), the pH100A will fit your needs.