... ,Easy to use 2.Auto zero and blank 3. Large LED displayer 4. Wavelength range: 325-1000nm Name:Visible SpectrophotometerModel:7221.CONTENT ... , Absorbance and Concentration modes.3.Auto zero and blank 4.LED display is large enough to read from any distance, ther ... .3%T Stability ± 0.002A/h @ 500nm Display 4 Bits LED Detector Silicon Photodiode Output USB Port & Parallel Port(Printer) Light ...