Bondo Body Filler cures fast, shapes in minutes and is formulated to be a non-shrinking and permanently durable material for repairing metal, wood, steel, aluminum, fiberglass, and concrete. Repairs dents, patches rust holes, leaks and fills in chips quickly and easily. Easy mix ratios make it convenient to measure. Spreads easily and sands in just 20 minutes. Finish auto body projects the same day you start! Compatible with all paint systems. Includes Red Cream Hardener.