This colour scale covers the range from colourless to brown and is used for grading of resins, shellacs and tar products.

The scale is based on a series of solutions made from varying proportions of cobalt chloride, ferric chloride and potassium chromate in hydrochloric acid solution.

142000 142000 Comparator instrument to bring the sample and the glass filters together for colour matching.
171010 171010 A standardised bench-top light source that guarantees constant and uniformed lighting conditions for colour matching.
For use with the Comparator 2000+.
243600 243600 4/36 Barrett Scale Disc, 1 - 6
606790 606790 5mm path length Series Fused Optical Glass