Lab Junction Spectrophotometer Digital Visible Spectrophotometer LJ-304 340-960 nm 10 mm to 50 mm Optical Path Length Absorbance % Transmittance and Concentration Measurement Ideal for Mineral Water Plant Drinking Water and Water Treatment Laboratory Analysis with Calibration Certificate complies USP Standards. Digital Spectrophotometer LJ-304 & LJ-305 are the most economical, reliable, rugged and accurate instrument for spectrophotometric analysis of any concentration. Digital Spectrophotometer LJ-304 & LJ-305 operates at a wavelength range of 340 nm to 960 nm. The output is available on a 3 ½ digit red seven segment LED display in terms of %Transmission (%T), Absorbance (Abs.), and Concentration (Conc.). This is useful instrument for Chemistry Labs, Pharmaceutical Industries, Colleges and University Labs etc.