This is the Donchian Channel expressed with a percentage cloud. Default 12.5% of the range will be filled at each edge, this helps to show reversal possibilities as price returns to the area between the clouds. This offers a usage to essentially fade the turtle trader system. That system is loosely based on the playing of the breakouts of the the channel... as you can see the that last turtle trade long in YM1! was and is off the charts awesome. I will look for the fall out of the cloud to short the market.