Meet Hulk, the biggest puppy you'll probably ever see

He may be only 18 months old, but this puppy is already double the size he's supposed to be.

Meet Hulk, a 175 lb pit bull owned by Marlon and Lisa Grennan of Carroll, New Hampshire. 

"The power of this dog is unrivalled. If he bit down on someone's arm with full power it would snap like a toothpick.''- Marlon Grennan, Owner of The Hulk

Hulk has grown up alongside Jordan, the Grennan's three-year-old toddler.

Jordan sleeps with Hulk (sometimes referred to as The Hulk,) rides on top of him and kisses his massive head. Jordan's parents say the enormous puppy is 100 per cent trusted with their young son because the dog understands when he's with family and when he should be on guard. 

Lisa, 24, has said on Facebook that the American Pit Bull Terrier breed is misunderstood, something she is trying to change. 

Canadians are familiar with the controversy surrounding the breed. In Ontario, a ban on pit bulls was implemented by the Liberals in 2005 under then attorney general Michael Bryant, who famously called them "ticking time bombs." The law was the first large-scale pit-bull ban of its kind in North America. 

The Brennan's are trying to shatter what they perceive as misconceptions about the breed. Marlon says he is frustrated that pit bulls are portrayed as an overly aggressive breed and hopes to change opinions.

Despite the criticism, the Brennan's pups are in high demand with clients in around the world. In fact, the cost of one of Hulk's sons could go for up to $30,000 USD, he says, and the owners have been offered $500,000 for Hulk himself. But Brennan, owner Dark Dynasty K9's, a family-owned kennel that breeds and trains American Pit Bull Terriers as protection dogs for clients worldwide, says there's no chance he's selling, calling the dog priceless.

On the Dark Dynasty K9's website, the couple makes clear that they are not running a puppy mill and that they vet the buyers of their puppies: "We proudly promote the well being and reputation of this working breed with each carefully raised puppy and well trained dog in our growing family. We are a member of the American Dog Breeders Association and the United Kennel Club."

In a recent Facebook post, Marlon wrote: "watch for us as we pursue the path of reality TV which will give us the ultimate stage to spread our message!"