Does anyone have this, or has anyone used this device? Here is a youtube video: There are also some accessories that go with it -- that are supposed to make it, e.g., slide easier on the rope. I think the primary use of this might be for top rope soloing (and then, only on shorter routes with extreme caution and another device as a backup). YMMV. I am always wondering whether it might also work to back up one's rappel. I know the standard action -- it weighs much more than an autobloc, and an autobloc is cheaper too. For the rich and the "don't care about weight crowd," is it possibly useful for any canyoneering applications?