The Badfish Re-Leash connects to a board like any other leash, with a velcro enclosure. The thing that makes this leash special is the design that attaches to the rider, actually to the rider's equipment - like a PFD.
On the end that connects to the rider, the leash is composed of a releasable snap-shackle, release cord & ball and carabiner. If I ever need to be released from the leash system, I just give the release ball a tug and it opens the snap-shackle- freeing myself from the board.
I am regular footed, so when I go to a staggered or surf stance, my right foot goes back. I attach the carabiner portion of this leash to my right side, on a solid strap on my river PFD. This makes sure that the leash doesn't get tangled and stays out of the way.
The leash has released everytime I've wanted it to, whether I'm sharing the leash & board or if I'm swimming in a rapid and need to be free'd up.
It's the only leash I'll wear on a river, as my opinion is it's the safest option our there.