New & Improved Power formula acid-free wheel cleaner; safe for all wheels The color changing formula activates when it comes in contact with the ferrous metals (iron) from brake dust or other dirt and grime. Wheel Cleaner Plus sprays on clear, then turns deep red or purple as it dissolves brake dust. Sonax Wheel Cleaner Plus should be used on cool and dry wheels. Product is ready to use, do not dilute with water. *Use caution when applying this product to anodized wheels and brake systems - test in an inconspicuous area prior to use. Use on a cool dry wheel in a well ventilated area. Spray on Sonax Wheel Cleaner Plus holding bottle 6-8 inches from the wheel surface. As Wheel Cleaner Plus emulsifies stubborn baked on brake dust and dirt, it changes from clear to red. Exceptionally dirty wheels may require agitation. Allow the product to work for up to 10 minutes. If product dries, simply re-apply. Rinse your wheels, preferably with high pressure water. SONAX is a worldwide car care brand manufacturing premium products for optimum maintenance, protection and rejuvenation of vehicles. With 70 years of continuous research and development SONAX car care products that last longer, perform better and shine brighter than the competition. The ever expanding line of SONAX car car products includes car waxes, interior and exterior cleaners, tire gels, vehicle paint cleaners, auto shampoo and more.