It will stick to new metal if prepped right, I've used a lot of it & have had a few issues with sticking, peeled my whole trunk lid off in one piece, don't know what I did wrong, but it's on the inside of my new quarters,which I stripped of primer(to find rust underneath)then used the metal ready to etch the put on the por 15, definatly finicky stuff, but once on it is TOUGH!
for shelf life put a piece of saran wrap under the lid & make sure it's tight!
they do mean it when they say follow the instructions, even with the few problems I've had(probably user error) I like the stuff, would maybe like to try eastwoods stuff or zero rust on the next car, supposed to be easier to use?
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