Inventors can get their inspiration from a variety of sources. In Bill Feldman’s case, it came from his dog, Henry.

Feldman, a Portland resident and former U.S Navy officer, launched a company recently to sell a unique wristband he designed that attaches to a dog leash to keep pet owners’ hands free while walking their dogs. It also eliminates the problem of an energetic dog yanking the leash out of its owner’s hand, he said.

The product is called Liberty Wristband, and Feldman is currently selling it on his website, libertywristband.com, Amazon.com and at pet-products retailer Planet Dog in Portland. He launched the product on July 4, a nod to his deep sense of patriotism.

“It’s extremely comfortable and extremely strong,” Feldman said. “It takes the stress out of holding onto the dog.”

The wristband, which retails for $29.99, is padded on the inside and is secured around the wrist with Velcro. A quick-release metal clasp on the outside attaches to any standard dog leash.

Feldman said he came up with the idea while living in Florida, shortly after he adopted Henry from a pet shelter.

“Henry was a 90-pound ball of energy and muscle,” Feldman said. “He was constantly pulling (the leash) out of my hand.”

Feldman initially devised the hands-free leash holder for his own personal use. The prototype’s design was radically different, as it was built around a fingerless glove. He later dropped the glove design in favor of a wristband, which is easier to put on and take off.

The wristband was so useful that Feldman wondered whether he should try to build a business around it. First, he researched the market to see if such a product already existed. To his surprise, it did not.

“I’m so proud that I was able to stumble on something that worked for me, and I couldn’t believe that no one else had developed it,” he said.

Once he determined that the Liberty Wristband was unique, Feldman applied for a patent, which is now pending.

While the idea for the product came relatively easily, bringing it to market did not, he said. The journey from prototype to mass production was long and arduous.

Challenges included suppliers and contractors missing deadlines and breaking promises, he said. What Feldman had hoped would be accomplished in six-to-eight months ended up taking two years, he said.

“For a guy who’s been at war and in countless military operations, this is the hardest thing I’ve ever done,” Feldman said.

He sought advice from the local SCORE chapter, which he said he found invaluable. Prototypes were tested with professional dog walkers. Once he settled on the final design, he located a manufacturing contractor in Scarborough to produce the wristbands.

Up until now, the company has been entirely self-funded by Feldman and an old Navy buddy, he said. Their goal is to raise additional funds to ramp up production.

Feldman said he hopes Liberty Wristbands will allow him to gain a foothold in the $62 billion-a-year pet products industry.

“Eighty million households in the U.S. own at least one dog,” he said. “The market is extraordinarily large.”

But for now, the company remains a small operation. Feldman is its only employee, and he has sold about 200 wristbands.

That should increase as word gets around about the product, said Jim Williams, store manager at Planet Dog where the wristbands have been for sale for about two weeks.

Williams said Feldman came into the store several months ago to show off the prototype and seek advice about how to proceed with his business.

“He was more or less picking my brain on a number of things,” Williams said. “I was impressed with not only the product but with him as an individual.”

It is not uncommon for local makers of pet products to approach Planet Dog about selling their goods, he said, but Feldman’s case was unusual because he had invented a product unlike anything he’d seen on the market.

“Here was a product that came to my door like nothing I had ever seen,” Williams said.

Feldman, who is prone to using nautical analogies, said any entrepreneur with an idea they believe in should persevere and not be discouraged by the numerous setbacks associated with launching a company.

“Stay on course like a ship at sea, and push through the squalls, and there are a lot of squalls,” he said.