... assay, absorption spectrophotometry, dual-wavelength method3. Temperature control system: PELTIER temperature control component, 25°C, 30°C, 32°C ... , 450, 492, 510, 546, 578, 630nm5. Quality control: QC data summary, store and draw QC diagram6. Open reagent ... 220V/50Hz11. International standard RS-232 serial port, for connecting to computer, optional to be connected external printer for printing test ...