This trick can be performed on a Bar to Bar rig, and on a Petit Volant rig with a Static Cradle catcher. It is too much strain on the shoulders to attempt it on a full sized rig with a swinging catcher.
Swing out and turn around. At the frontend, turn to catch the second bar/catcher without letting go of the first so you end up hanging between both. Once you are finished, you can either let go of your original bar and swing down with the other bar/the catcher, or you can return the way you came.
You can find out more about this trick in my books:
Thanks to Alain for providing a video for this page.