Long Hauler Cradle Back Harness
From the Manufacturer:
Kurgo’s Long Hauler Joring Harness allows your dog to use its body weight to pull you, without hurting itself. The harness also helps your dog distinguish when to pull and when not to pull. Unlike other competitors, Kurgo’s Long Hauler Joring Harness is modeled after dog sledding harnesses rather than a running one, keeping your dog comfortable while taking advantage of your dog’s maximum pull potential.