Substrate Surface TreatmentCold Rolled Steel and Alumimum MEK Wipe, Grit Blast, MEK WipeSheet Molded Compound (SMC) 320-grit Sandpaper, Dry Rag WipeStyrene Butadiene Rubber (SBR) Primed with LORD 7701 Surface TreatmentNatural Rubber Primed with LORD 7701 Surface Treatment