Originally Posted By: dblshock
ITW says 'Tough coating serves as an excellent protective primer that you can paint over'.... so I read a topcoat is optional but not required.
I've used and tested these products, if you want it to last a primer and top coat is the way to go. Leaving it as it will result in rust, especially in the rust belt, painting over it will result in rust, only it takes longer. Priming over it and painting it yield the best results.