After using some Rust Bullet on the inner fenders of the 40Ford a couple months back, I closed the can back up, forgetting how some other similar products I've used before had a tendency to stick (read: WELD) the lid to the can!
Well sure enough, the RustBullet sticks SO WELL and dries SO TOUGH, that the lid was literally welded to the can - and no amount of prying was going to separate the two!
So.... I highly recommend you take precautions to either not to get ANY of the RustBullet product between the can and a lid (as per their FAQ's and application instructions), or you can expect the above result! As well, there are a few common practices that will help to avoid this, including placing a barrier between the can and lid, like a piece of thin plastic (Saran Wrap, thin bag, etc), or, transferring the remaining product to a glass jar just large enough so as to minimize the amount of air stored within, as well as with a good, airtight lid.
But, since I didn't heed these recommendations, I had to revert to plan C: poking a hole in the lid to pour out what I needed....
The can can be sealed with some duct tape until you are done the job, with the remainder then transferred to a glass or plastic container and kept in a cool spot until needed again.
Now although you may think it a hassle to have a product that does this, it certainly proves RustBullet's power to STICK to metal so well - and dry so hard - that it should be considered a KEY element of your rust-proofing arsenal. It's definitely earning an important place in mine!