The budget friendly portable 4-wavelength Colorimeter is great for  determining the concentration of unknown solutions usint Beer's law, or studying changes in concentration vs. time. Our Colorimeter features one-button automatic calibration. Fifteen 3.5 mL cuvettes are included.

Range: 0 to 3 (absorbance)
Useful Range 0.05 to 1.0 (absorbance) and 90% to 10% transmittance (%T)
Wavelengths: 430 nm, 470 nm, 565 nm, 635 nm
Resolution: 0.035 %T
Supply voltage: 5VDC +/- 25 mV
Supply current (typical): 40 mA
Power up time: 700 ms (maximum)
Output voltage range: 0 - 4 V
Transfer function: Vout = 0.035 x (%T) + 0
Stored calibration values: Slope = 28.571; Intercept = 0