Is your vehicle's paint rough or gritty? Clay removes the contaminants you can't see but can definitely feel. When contaminants get a chance to oxidize, they create rust. Advanced oxidation is considerably harder to get rid of and usually takes some paint with it. OER Clay Bars remove such contaminants, pulling out foreign particles for a smooth finish. One medium-duty bar can do 8-10 vehicles. This clay does not break into pieces like low-quality clay; its elasticity helps eliminate contaminants quickly & effectively.