I am gonna take a good educated guess and say those are black powder only. Now I have been able to get some "special crackers" called Hillbilly firecrackers in strands of 200 and 500, and those contain flash powder, but as soon as stores get them, they get pulled off by local authorities. "To large of a cracker to be sold as a Class C Item." I would say they are 3 times the size of a normal firecracker, and at least 5 times as loud, with a bright flash. but again like i was saying usually as soon as 1 place gets them they get removed off the shelf. When I was down in New mexico the lady I had dealt with told me she had some 1 pound sky rockets. that were recently removed from the shelf by local police. So she sold them to me for the cost they recieved them for. Very nice rockets I must say. They went about 300 to 400 feet High With Very Loud Reports Each one did something different. one was a Plum, another Chrysanth. another called Double Bang.
I am going to start taking requests on finding, or personally making videos of fireworks people would like to see. I plan on Starting the 2nd week of March. So if anyone wants something specific Please send me Private msg.
thanks