Makes removing stubborn stains from lab glassware safe and easy by eliminating messy mixing and boiling. Chromerge leaves surfaces chemically clean, protects glass and gives a perfect meniscus for precise volumetric work. Each pre-mixed bottle contains 25ml of chromium trioxide in solution which, when mixed with  a 2.5L bottle of sulfuric acid makes a super-efficient glassware cleaner. Once mixed, it can be stored and re-used until it turns green, indicating loss of effectiveness.