John Westlake, 38, said he thought it would be “a funny way of killing some time” while he and wife Sarah-Jane waited for a takeaway pizza. The footage has been widely shared and viewed more than 17,000 times on social media.
It shows John flashing passing vehicles with his mobile phone whilst sat inside the camera’s casing.
John was on a caravaning holiday with his wife, kids and mother in Towyn, north Wales, when he carried out the strange stunt on Thursday.
And the father of two told North Wales Live: “We were waiting outside for our pizzas when I noticed a hole in the back of the speed camera.
“At that point I thought it would be a funny way of killing some time to climb up and flash the passing cars to see if they’d slow down.”
John, a joiner from Merseyside, was branded “naughty” on social media for the behaviour.
One Facebook user wrote: “Very naughty. But thank the Lord in such difficult times we still have characters like him.”
Another said: “Not funny and extremely dangerous.”
A third posted: “What an idiot.”
But John said the bizarre antics kept he and his partner “entertained”.
“We were just having a laugh really. Every car I flashed slowed down afterwards – it kept us entertained when we were waiting for our food,” the joiner continued.
“I think people relate to it because no one likes speed cameras.
“I flashed one person who went by in a mobility scooter and told them to slow down.
“I just took a run-up and managed to climb in. I was quite surprised the next day, when I saw the speed camera, that I had managed it to be honest.”
And John says he’s received messages and friend requests since posting the video online.
However, speed cameras have been introduced along the road – the A458 – because it is a busy area popular with tourist families with young children.
There is a 30mph speed limit along the road, which runs adajacent to caravan parks and campsites.
In some places, including Cornwall, a debate rages whether speed bumps are more effective than speed cameras.