When UK Skunkworks opened in Gravesend a year ago, the bosses behind the business knew they were taking an enormous risk.

It coincided with the company’s decision to axe its lucrative online operation following complaints from parents that legal highs were being sold to their underage children.

But Skunkworks says it has flourished at its branch in Parrock Street and more customers are coming through the door, according to representative Eugene Lusardi.

Mr Lusardi, based at the headquarters in Northfleet, said; “It became clear that you cannot regulate online. Anyone can tick a box and say they over the age of 18. And we all know young people can be misguided.

“We are very strict about who we sell to. An 18-year-old may be able to walk into a shop, but we don’t even allow them to browse.”

The franchise was set up more than 10 years ago and now has 14 shops across London and the south east, including one which opened in Chatham two weeks ago.

Mr Lusardi, 25, has issued a challenge to critics of legal highs - “don’t judge us until you have come and met us”.

He added since opening in the town centre they had received “absolutely no opposition”.

The north London-based graphic artist said: “We work on the basis that we are giving adults the freedom of choice - people have been smoking for decades, they choose to do so.

“I couldn’t begin to sum up our client base. It is all ages from students to people in their 60s.”

On reflection, Mr Lusardi believes that the word “skunk”, associated with the class B drug cannabis, may have given it a bad reputation.

He said : “If you look up the dictionary meaning of the word, one of its meanings actually is “a group of people who work together to achieve great results”.