Flash powder is a powder comprised of Potassium Perchlorate and Aluminum Powder. It's called flash powder for it's rapid expansion, it literally flashes out of existence with a bright flash of light. Flash powder is used in most exploding firecrackers but in small amounts. The legal limit for the U.S. is 50 milligrams, M-80s and other such types of firecrackers contained the same powder but in larger quantities. M-80s usually contained 7 grams of flash powder. Flash powder is so powerful that in larger amounts it will explode upon ignition without the need for a shell for gasses to build up in.
"Wow! That flash powder really makes for good firecrackers, it just ripped the hood of that car off!"
" I know, good thing we used 4oz of it, I wounder what 8oz would do?"