The Traildog is for backpacking with your dog. The dog is pulling a travois with a wheel in the rear. The luggage fits over the wheel like the luggage rack and pannier of a touring bike. Two shafts go from both sides of the axle to both sides of the dog where they attach to the dog's harness. They loop over the dog's back the way pulk shafts and sacco cart shafts do. With the Traildog the dog can carry weight more easily than with saddle bags. You put baby in your back pack and put gear in doggie's backpack.  And away you go.