The Lamotte 1925 user-friendly Chemical Oxygen Demand (COD) COD3 Plus Colorimeter has direct reading for on-site water analyses. It features pre-programmed tests, automatic wavelength selection, menu-driven operation, and large backlit display screens. The analyst can simply select the test and put in the sample with reagent. The microprocessor, which selects the wavelength, also allows the user to load up to 25 tests for analyzing custom reagent systems.