transform between hl/hrc/hrb/hb/hv/hs. store the latest 250 groups measurements. select measured material and way by key. can show measurements repeatedly to remove the large errors. use usb data output with connection pc. provide bluetooth data output choice. Product parameters Accuracy Display error 0.8% at ld=900 Measuring range:200~900 hld Measurable material:9 different common materials Operating temperature:-10°c~50°c°c Relative humidity:90% Size:140x70x30 mm Power supply2x1.5vaaa um-4 battery Weight:130 g (not including batteries)