KLETT SUMMERSON COLORIMETERS Photoelectric colorimeters that use specific light filters to give readings on a unique Klett Scale. The readings are directly proportional to the concentration or optical density of a solution, in accordance with Beers Law                                                                                                                               Bel-Art Products (USA)  Colorimeters   Features: The precision suspension wire Galvanometer has an illuminated logarithmic scale, graduated from 0 to 1000 Units are supplied with BLUE Filter for 400 nm to 450 nm and GREEN Filter for 520 nm to 580 nm wavelength ranges Fourteen additional filters are available for complete visible range.       800-3 Model Description 800-3 Clinical Model, uses standard 14.25mm x 125 mm Test Tubes 900-3 Industrial Model, uses rectangular Solution Cells 20/40 mm and 10/40 mm The solution cells can be used in either of two directions so measurements can be taken at depths of 10 mm, 20 mm or 40 mm   900-3           Bel-Art Spares & Accessories           Model Description Klett 801 Test tubes for Klett 800-3 (12/pkg) Klett 901 20mm x 40mm Solution Cell for Klett 900-3 Klett 902 10mm x 40mm Solution Cell for Klett 900-3 Red Filter Color Filter for Klett Colorimeter Blue Filter Color Filter for Klett Colorimeter Green Filter Color Filter for Klett Colorimeter Photocell For Klett Colorimeter Projection Lamp For Klett Colorimeter Filter Holder For Klett Colorimeter Galvanometer Lamp For Klett Colorimeter Note: Fourteen additional filters are available for complete visible range.