New Knex RBG* System (i Think).

EDIT: poorly found a con, it only shoots at low presure, or else trigger breaks.
if sombody know to fix it, plz comment >.<

i dont know if it already has been posted, but i found a new way to make RBG's*
it's simple and good system.

i need a name for this system, dunno how to call it...

plz rate and comment. (*rubber band gun)