AI5529 Includes Only:PH850-HF Portable pH MeterSwiss LabSen 831 pH ElectrodeMP500 Temperature probe designed for measuring strong alkaline solutions.Features:Long service able to measure solution containing HF for about 1000 times.Self-Diagnosis of out-of-range value and electrode invalidation auto. calibration electrode slope display Auto. power-off easy parameter settingRugged Structure Design: IP57 waterproof rating; Soft silicon case gives you a firm and comfortable gripPowered by AAA batteries; the foldable stand also allows use as a benchtop meterApera Instruments PH850-HF Portable pH Meter is designed for measuring solutions containing strong acid solutions containing hydrofluoric acid and storage battery solutions. The equipped Swiss LabSen 831 3-in-1 Glass pH/Temperature Electrode adopts a special HF glass membrane which is resistant to HF corrosion and is capable of measuring solution containing HF for about 1000 times. The probe also works well in high-temperature samples (up to 100°C/212°F). The unique LabSen blue hemispheric glass membrane has a faster response rate better repeatability and built tough - highly resistant to general impact. The Meter has a ±0.01 pH accuracy in a range of 0-14 pH and Temperature Range: 0 to 100°C(32 to 212°F).. Auto Calibration with auto-recognition of up to 12 kinds of buffer solutions temperature. Compensation and supports stable reading/auto-hold display mode. The meter's digital filter technology improves response time and accuracy. Smart Self Diagnosis reminds of out-of-range measurement incorrect calibration and electrode invalidation. Other functions include auto. calibration auto. lock easy parameter setting pH electrode's slope display auto power off etc. Reliable Structure Design: foldable stand allows use as a benchtop meter; soft silicone case gives you a nice firm grip; connector protection cap IP57 waterproof rating; Powered by 3 AA batteries.