Wheel Woolies 3 Piece Set is a 100% metal free wheel cleaning set designed to remove road grime and brake dust without damaging your wheels. Perfectly designed for cleaning those hard to reach spots on wheels of all shapes and sizes. Safe for wheels and rims of all finishes. Constructed from 100% polypropylene to prevent scratching and damage to the surface area being cleaned. Dense absorbent synthetic wool microfiber eliminates wheel cleaner splatter and can stand up to any cleaner. The brush sizes include: (1) 18 inches, (1) 12 inches, and (1) 8 inches. Large Wheel Woolie is great to reach deep into wheels and for cleaning the wheel wells on vehicles and RVs. Medium Wheel Woolie is great for smaller wheel gaps, air diffusers, door jams, and engine areas. Small Wheel Wool is great for small gaps such as grills and narrow spoke wheels.