Board Thread:Off Topic/@comment-26397825-20160329001315/@comment-27425734-20160406030236

It's connected to a cable which is flexible, but strong. The cable is attached to the launcher, and is retractable in a similar manner to a grappling hook gun. The blades stop spinning once he takes his finger off the trigger. He hits the trigger again to retract it.

As for controlling it, part of that has to do with his Semblance which is based on influencing the probability of certain events within reason. The other part is just years of practice, and many mistakes, some worse than others.

I admit this is a "rule of cool" weapon since it defies logic and physics for him to be able to control this thing as well as he does. There is still a chance that he can kill himself though, but it's much lower than it should be thanks to his Semblance.