Ruffwear Double Track Coupler

This is a great idea and I can appreciate it being the owner of two super-human labs. However, for over a year I've accomplished the same thing with the Ruffwear Roamer leash. I like it because I've used a retired carabiner to walk both my dogs at once on this single leash. It has a handle loop at the bottom which I hook to and, boom, both are at the end and there is only one leash. See it here-- http://www.backcountry.com/ruffwear-roamer-leash