M25 Antique Black is designed to make multi-metal finishing simple and easy. There is no need to resort to several different solutions for different metal surface because this product is said to produce an attractive range of brown and black finishes on both solid and electroplated surfaces. It represents a new option for finishers who work with both copper and brass and zinc allows. It is a concentrate that is mixed with water at 10-20% for blackening or browning copper and brass alloys and at 5-10% for blackening zinc. The product works at room temperature and is said to form a tightly adherent conversion coating, with immersion times ranging from 30 sec to about three minutes, depending on the depth of color desired. It can be used in any size finishing operation and is said to be easy to control by simple titration.