This special concentrated formula is the best we have used, involves no buffing and resists the tarnishing other cleaners seem to do immediately after cleaning. Removes tarnish, bacteria, and normal water stains associated with watercooling. Takes about 5 minutes to receive the result above. Very easy to use and takes about a dime sized drop to work the whole waterblock. The kit includes 1oz of copper cleaner, and a brush. 1oz can effectively clean 20-25 waterblocks depending on their size. Directions: 1. Shake Well before use 2. Dampen brush with water and apply cleaner to the waterblock and work it with the brush untill all areas are cleaned. The cleaner starts working immediately. 3. After desired cleaning is done Rinse immediately with warm water. 4. Thoroughly dry before assembly As a precaution keep away from plastics and laquered surfaces. Prolonged contact with skin may cause irritation, so it is best to wear gloves during the cleaning.