How the military's folding canoe has stood the test of time
It has been used by the military for decades, is the boat of choice for penetrating enemy lines without drawing attention and was used by Royal Marines for raids in the Second World War.
Any guesses? It is the Klepper folding canoe - probably not what you were expecting.
Saul David, a military historian, told Forces News about how these canoes have stood the test of time and why the military keep using them.
He explained they can "collapse completely inwards" - making them extremely useful.
However, despite their extreme stability, they are quite heavy, meaning they need two people to paddle.
Mr David explained the person at the back steer and match the pace of the person at the front, who determines how fast the canoe goes.
"He decides on the pace and I have to follow his pace so he's like dipping the oars in like this and I have to keep exact pace with him," he said.
"The whole point about two-man Kleppers is it's about coordination and you can move a quite a decent clip in the water."
"If you're a sailor six or seven knots is a pretty decent speed for a yacht - we can get that if the wind and the sea are in the right direction."
The canoes were made famous by the Cockleshell Heroes - a group of Royal Marines who, after paddling 60 miles to Bordeaux, took out a number of German ships with explosives.
"So it seems like they're not going to deliver that much force but actually these canoes could deliver quite a punch," Mr David said.
"Of course you can only take two guys but you can actually carry quite a few explosives, different bits of kit on board these vessels."