YM-901 PenpHTestrWPRange: 0.0014.00pH,Resolution: +/-0.01pH,Accuracy: +/-0.03pH,Temp.C: 0-50,(ATC)Calibration: Two-pointat6.86pHand4.01pH(or7.0pHand4.01pH)Features: Automaticswitch-offfunction:After10minuteswithoutpushingbuttons,themeterwillbeswitchedoffautomatically.LowbatteryAslongasthereisanydisplay,theaccuracyisguaranteed.BatteryLife: DC4x1.5VFlug:FixedelectrodeCarton:100pcs/CTN --IamthemanufactureroftheYMInstrumentCo.LtdinChina.