[ame="http://www.youtube.com/watch?v=fFYxM0cdmEY"]http://www.youtube.com/watch?v=fFYxM0cdmEY[/ame] Not sure what category this would fall into. This would be connected to slingshots because of the black, special heavy Thera-Band tubes that I used. Although I didn't design it for high velocity, it does pack a pretty good punch. I actually designed it to launch 1" glass marbles that are hollowed out and filled with what ever you can think of (liquids, explosives, etc). Currently, its set up to launch metal projectiles. I am working on a fitting that will accept the glass marbles.