Klett Bio Colorimeter, a device used in colorimetry to measure the absorbance of particular wavelengths of light by a specific solution. Colorimeters are commonly used to determine the concentration of a known solute in…

Electric-powered meter with instructions housed in wooden box. Movable components within box: two (2) slide glass filters (1 with red, green, and blue slides; 1 with orange, green, and blue slides); one (1) encasing to…

Wooden box with metal instrument panel on top; four small black rubber feet on bottom; front of wooden box contains printed instructions and folds down to show inside of instrument; rectangular wooden area attached to…