It looks like the Eastwood rattle can releases the activator into the can in one burst, which means you have to use the whole can at once. Virtually all "epoxy" paints have a pretty short pot life before the chemical reaction happens and the paint cures- - - -which my friend who owned a body shop learned the hard way back in the 1970's when he left a little IMRON in his spray gun overnight. The stuff cured into a solid mass that couldn't be removed and he had to buy a new spray gun!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!