HI98140 is a portable Calibration Check™ pH meter that utilizes HANNA's SMART electrode technology. SMART electrodes incorporate a chip, which stores the calibration data performed with a specific instrument. When the "SMART" electrode is attached to the meter again, it is automatically recognized. This allows the operator to optimize time and efficiency with unsurpassed safety. It also avoids erroneous measurements taken in the event the pH electrode is substituted after calibration. pH Calibration Check™ Electrode Diagnostics Waterproof Up to five point pH calibration Log on demand (500 samples) GLP features Auto endpoint User-selectable "calibration time out" Backlit, multi-level LCD display Tutorial messages on LCD Opto-isolated USB BEPS and % battery life on display; Battery Error Prevention System alerts the user in the event that low battery power could adversely affect readings Range pH: -4.0 to 20.0 pH; -4.00 to 20.00 pH Range Temperature: -20.0 to 120.0°C (-4.0 to 248.0°F) Resolution pH: 0.1 pH; 0.01 pH Resolution Temperature: 0.1°C (0.1°F) Accuracy: @ 20°C pH: ±0.1 pH; ±0.01 pH Accuracy: @ 20°C Temperature: ±0.2°C (±0.4°F) excluding probe error pH Calibration: up to three point calibration with seven standard buffers available (1.68, 4.01, 6.86, 7.01, 9.18, 10.01, 12.45), and two custom buffers Temperature Compensation: automatic, -20 to 120°C (-4 to 248°F) pH Electrode : HI 1618D PEI body, pre-amplified pH electrode with “SMART†technology, internal temperature sensor, DIN connector and 1 m (3.3’) cable (included) PC Connection: opto-isolated USB with optional HI 92000 software Power Supply: 1.5V AAA (3) / approximately 200 hours of continuous use without backlight (50 hours with backlight). User selectable auto-off (5, 10, 20, 60 minutes or can be disabled) Environment: 0 to 50°C (32 to 122°F); RH max 100% Dimensions: 185 x 72 x 36 mm (7.3 x 2.8 x 1.4’’) Weight: 300 g (10.6 oz.)