3M™ Piranha™ Advanced Finishing Putty, 05821, 24.0 oz Tube, 6 per case Designed for use as a skin coat over plastic filler to fill pinholes, sand scratches, low areas and other imperfections. Cures tack-free in 30 minutes. Grips tight to galvanized steel, sanded paint, aluminum, steel, SMC and Fiberglass. Extremely easy sanding. Flowable and brushable. Non-staining.