Replaceable 122 mm (4.5") penetration probe. Automatic temperature compensation. Lightweight and portable. The HI 98331 Soil Test is a pocket tester specifically designed to directly measure soil conductivity and temperature. With a temperature sensor in the penetration probe, measurements are automatically temperature compensated. The conductivity range can be calibrated at one point and is designed to be performed in a standardized solution. HI 98331 Soil Testis supplied with HI 73331 penetration conductivity probe, calibration screwdriver, batteries. Range: conductivity: 0.00 to 4.00 mS/cm (dS/m),Temperature Range : 0.0 to 50.0 degree C. Resolution: Conductivity: 0.01 mS/cm, Temperature: 0.1 degree C. Accuracy: Conductivity: +/-0.05 mS/cm (0.00 to 2.00 mS/cm),+/-0.30 mS/cm (2.00 to 4.00 mS/cm), Temperature: +/-1 degree C. Temperature Compensation: Automatic, Temperature coefficient (beta) fixed at the rate of 2 percent degree C. Calibration: Manual 1 point. Probe: HI 73331 122 mm (4.5") penetration. Battery type: 4 by 1.5V. Environment: 0 to 50 degree C. Measures 6-25/64" length by 1-19/32" width by 1" height. Weight: 3.5 oz.