Star brite Epoxy Aluminum Putty Stick - 4 oz [87004]Waterproof Epoxy Aluminum Putty Stick 4 oz Provides quick, permanent repairs on aluminum surfaces, even underwater. Designed for aluminum boats, RV bodies, fuel tanks, gutters, and storm doors. The high density formula bonds within minutes and withstands extreme temperatures and pressures. Directions: Clean roughen surface. Cut off the needed putty. Mix with wet hands until one color (1min). Apply to the surface within 2 minutes. Push into cracks