LR COD Vials Mercury-Free Method: Dichromate Reactor DigestionLow Range COD (Chemical Oxygen Demand) vials comes in a cardboard box and contains 150 vials, enough to perform up to 149 tests and instruction book. All COD Kits require the use of a Digestor Block and the V 2000 Photometer, an A 7320 COD Photometer, or a spectrophotometer capable of accepting a 16 mm round cell. Photometers sold separately. A fresh reagent ampoule blank must be prepared for each series of tests; therefore the number of samples that