The Society for the Prevention of Cruelty to Animals in New Zealand has slammed a dog seatbelt company after video of dogs strapped onto it went viral. The activists say the belts are "not appropriate".

In the video, the product "Rocketeer Pack", made by ZuGoPet and certified by The Center for Pet Safety in the US, is used for demonstrating the harness.

"I've been cringing every time I see it come up on social media," Jessica Beer, head vet at SPCA Auckland said, according to Fairfax Media's Stuff website.

"They have different body shapes, they would be quite stressed by using it."

Beer also said that people are following a trend in which they tend to "baby-fy" their animals.

"It is not OK," she says. "I strongly advise not to copy that video."

But the pet company says that the product is a "patented pet safety car seat for dogs 25lbs and under" which is "designed to protect your dog and family in case of an accident".

According to Beer, the 'Rocketeer Pack' product meets American safety standards.

The vet has advised pet owners to transport their canines in a pen or keep them in a less restrictive manner in the back-seat of the car, the website reported.

She says that with an increase in the number of people taking their dogs on road trips, there is a demand for pet-related travel accessories.

"We're trying to move towards a more family pet-friendly holiday lifestyle," Beer said.

According to Beer, the key for a stress-free travelling with the animal is to really understand dogs and to recognise signs of uneasiness.

"We're treating them like the individuals that they are. They're mammals. They can get scared, they can get sick. They can probably go through the same emotions as a kid would, so cater for their emotional requirements, just as you would with a kid," she said.

"But don't strap them in like a baby would be the takeaway from that," she added.