My dog, Ace, is a bit of a puller. If you have one, you know what I mean –- during leashed walks, she prefers to lead. We used clicker training in our puppy obedience classes to teach Ace basic commands like sit, leave it, drop it, and come, but walking on a loose leash always seemed too challenging.

Recently, I dug out that dusty clicker, watched some YouTube videos, and started training her to walk on a loose leash. Though a slow process, I’ve seen steady progress and am hopeful we will continue to walk more harmoniously with all of our limbs intact.

Naturally, I was curious to give the ThunderLeash a spin. From the makers of the archetypal ThunderShirt, the ThunderLeash promises to reduce pulling by exerting gentle pressure around your dog’s midsection when she pulls, signaling for her to chill out.

The ThunderLeash’s design is pretty ingenious, as it can be used as a plain leash or as a harness. It has a special piece of hardware that rests between two adjustable pieces of metal. The leash wraps around your pet and is threaded through this hardware. The hardware is clipped to your dog’s collar. When your dog pulls, the leash tightens against the adjustable pieces of metal so that pressure is exerted, but not too much. As I walk Ace on a harness every day, I like the idea of the harness and leash being one piece –- that’s one less thing to worry about forgetting when I’m running out the door.

Ace has been walking with an Easy Walk Harness since she first set paw to pavement. This device also promises to squelch pulling by gently tightening around your dog’s chest, though the Easy Walk employs a martingale-style design to achieve the tightening.

I never found the Easy Walk Harness helpful in reducing Ace’s pulling –- like a tiny tank, she simply pulls forward with the harness snug around her chest. We continue to use the harness mostly because Ace is a Boston Terrier, and brachycephalic breeds benefit from using a harness to avoid the airway restriction that can come with attaching a leash to a collar.

Given my experience with the Easy Walk, I approached the ThunderLeash with some skepticism. I had been hurt before by the promises of a harness with a catchy name. How would the ThunderLeash compare?

Upon removing the ThunderLeash from its package, I was immediately struck by the obvious quality of the leash’s materials. The sturdy flat nylon feels strong in my hand, and the hardware is heavy-duty. I especially like the slightly padded loop handle.A blue ThunderLeash logo ribbon is sewn to one side of the leash. I’m not crazy about this detail –- surely there is a more attractive way to brand the leash that is in keeping with its otherwise sleek design.

The ThunderLeash comes with straightforward, illustrated instructions for fitting the leash as a harness. With a few minor adjustments, Ace was in.

Walking Ace on the ThunderLeash was a bit awkward. Although we used the size small, which is recommended for use in dogs between 12 and 25 pounds (Ace is a whopping 15), the main piece of hardware was too large and heavy for the harness to stay in the proper position while walking. Specifically, the bolt snap was too long, pushing back the part of the harness that loops around her torso. Given the weight of the hardware, it slowly rotated from the middle of her back to her side.

I tried adjusting her collar and the ThunderLeash itself, following the instructions suggestion to be able to slide two fingers between the leash and Ace’s chest, but I wasn’t able to get a good fit. I wondered whether this is a problem isolated to small dogs, but one recent online review included a similar criticism for a much larger dog (an Australian Shepherd) using the size large.

When I was able to get the harness to stay in the correct position for a minute or two, I did not notice an appreciable difference in Ace’s pulling. As with the Easy Walk, which comes in several sizes and fits Ace properly, she simply tolerated the feeling of the harness tightening and plowed forward.

In the end, I found the ThunderLeash to be an attractive, promising, yet ultimately unsatisfying harness to help Ace with her pulling. I am hopeful that differently shaped dogs might have had better experiences with the fit, and therefore the performance, of the ThunderLeash. For now, Ace will continue to rock her ineffective Easy Walk Harness as she happily gulps down liver treats with every snap of the clicker.

Dogster Scorecard for the ThunderLeash

• Quality: No doubt about it, this harness is built to last.
• Style: Funky branding doesn’t overshadow sleek simplicity.
• Function: Disappointing -– perhaps due to poor fit, the ThunderLeash was no match for Ace’s pulling.
• Creativity: A unique, convertible design helps this harness pull away from the pack.
• Value: The price is right given the quality of the materials.

Bottom Line

With a generous 100 percent satisfaction guarantee, the ThunderLeash is worth a try to curb your dog’s pulling. If it doesn’t work out, you can always enroll him or her in the Iditarod!

Now it’s your turn, Dogster readers: Have you used the ThunderLeash with your pup? Did it transform your daily tug-of-war into a proper walk? Or did you have similar difficulties with fit and performance? What is your favorite harness for your dog? Let us know in the comments!

Also: What products would you like to see reviewed in this column? Any dog-related doohickey except food or treats is fair game!