The impeccably-dressed South Korean flipped a tyre sideways, and with a deft sweep snapped a curious, pastel-shaded device onto the hub.
"Fitted in seconds," he said with a flourish, drawing nods of approval from Swiss onlookers all too used to their annual battle to preserve their fingers as they fix snow chains during the Alpine winter.
Welcome to the International Exhibition of Inventions in Geneva which bills itself as the biggest of its kind in the world.
Showcasing innovations from the plainly practical to the charmingly oddball -- all of which much be patented to be allowed a berth -- the annual fair's 41st edition kicked off this week and runs until Sunday.
It has drawn 725 exhibitors from 45 countries, with lone inventors making up a quarter and the rest from small companies, research institutes and universities.
"We only present new items, never seen before," noted Jean-Luc Vincent, its founder and president.
Past success stories include flexible lighting for decorations, stairlifts for the disabled, inflatable neck cushions and clips to hold a glass to a plate at parties.
A key goal of exhibitors -- who pay an event fee of up to 1,200 Swiss francs (980 euros, $1,285), booth hire not included -- is to hit markets. Industrialists and distributors make up almost half of the 60,000 visitors.
"The rhythm of innovation is accelerating and the competition is out there, inciting companies to buy inventions from outside, rather than develop them themselves," said Vincent.
Touring the fair offers insights into the inventor's art.
Ryu Dae Ryeong, mastermind of the "Running Tortoise" snow chain, said the seed was planted in 2005 when he was a professional soldier in South Korea.
"I was watching conscripts trying to fit chains in the winter. Then I came out of the army in 2010 and worked as a taxi driver, and I was the one having to fit chains," Ryu told AFP.
"It took me three shots to get the prototype right. Now I'm looking for a factory so we can start making them right away," he added, saying he foresaw a price tag of 310 euros for a set but staying cagey on likely production costs.
The inventors span the generations.
Irishman James Dower, 77, sat astride his "Tilt and Turn", a sturdy, petrol-powered tricycle whose trick is a flexible axle.
"It's a very simple design really. Nothing can go wrong with it," Dower told AFP.
"I'd been thinking about this from my young days. I'd had problems with three-wheelers, they'd topple when they turned. But four-wheelers needed suspension. This is the solution."
Dower's trike is mainly aimed at farmers -- he cited advantages such as a cost of less than 2,500 euros, and the power to pull weights of a quarter of a tonne -- but he said he saw potential for electric versions in urban areas.
"It's not my first invention. I had one before, an automatic gate for pig stalls, way back in the 1970s. But it didn't really take off," he added.
At the other end of the age scale was 17-year-old Malaysian Hafizuddin Abdul Rahman, whose electricity system uses decomposing garden soil in place of batteries.
"We wanted to show that soil is a way to produce power. Dry cell batteries use toxic chemicals. And there's an abundance of soil," Rahman explained.
"This started out as a school chemistry project. We invented it last April. I'm here to get experience. This is just my first invention, but my next one is still a secret," he said.
The inventors are grouped by nation. In the French section, Paul Chavand's enthusiasm for his "Rollkers" 10-kilometre-per-hour skates was infectious.
"I got sick of new technology, so I decided to focus on good, old technology," he told AFP, explaining how he uses a similar concept to traction-powered toy cars to give power thanks to the wearer's own weight and motion, while also preventing the feet from sliding back.
Chavand said he invested 10,000 euros of his own money in the project and was leveraging 100,000 euros from investors.
"If we find a manufacturer, this could be on the market within 18 months," he said.
He bristled at the mad scientist label sometimes stuck on inventors.
"We always get treated like we're crazy. It really annoys me," he said.
The underlying message is that for every problem, there's a solution.
Indian P Mahalingam was pitching his "WeeWee", a small tube that enables women to urinate standing up like men, with gains for hygiene, lower water use from flushes and discretion.
"If I can talk to the corporates, people who are in sanitation, then I'll have done what I'm looking for," he said.