The Transmission Attachment mounts on the front panel of the spectrophotometer. It has a current-regulated light source and optics to measure the spectral transmission of filters. Irregular shapes, such as sunglasses, can be measured to determine their effectiveness. Power for the light source is supplied by the spectrophotometer.

Similar to the filter transmission attachment for liquid-holding cuvette for chemical and biological analysis. The carrier supports five cuvettes. Since the transmission data is sent directly to the controlling computer, immediate analysis of the sample is possible. A calibration curve can be designed into the software to give immediate analytical values.