The Extech EC500 is a waterproof, handheld ExStik® II meter combining a rugged flat surface pH electrode with an autoranging high-accuracy conductivity cell. Dynamic cell-constant technology enables measurement of five parameters—conductivity, TDS, salinity, pH, and temperature—using a single electrode.

pH range 0.00 to 14.00 with 0.01pH resolution and ±0.01pH accuracy. Conductivity measures autoranging from 0 to 199.9µS/cm, 200 to 1999µS/cm, and 2.00 to 19.99mS/cm with ±2% full scale accuracy. TDS measures from 0 to 99.9ppm, 100 to 999ppm, and 1.00 to 9.99ppt. Temperature range -5 to 90°C with ±1°C accuracy. Nine selectable units include pH, µS, mS, ppm, ppt, mg/L, g/L, °C and °F.

Advanced features include adjustable conductivity-to-TDS ratio from 0.4 to 1.0, fixed 0.5 salinity ratio, and Extech's RENEW feature that alerts users when calibration is needed or electrode replacement is due. IP57 waterproof rating, stores up to 25 labeled readings with analog bar graph trend indication. Auto power off with disable function conserves battery life.

Complete with electrode, protective sensor cap, sample cup with cap, four CR2032 batteries, and 48" neckstrap. EC510 kit also available with calibration standards and buffers. Applications include water treatment, wastewater, groundwater, aquaculture, and fisheries management.