When they are in uniform, they can be identified by their red berets.
Yesterday, a group of 29 men - two current commandos and 27 former ones - traded their combat boots for running shoes as they came together to raise money for charity.
They were in the Keppel Land Water Challenge, which was part of the annual Green Corridor Run, and the team raised more than $600 in all.
Participants had to carry containers of water through the whole 10.5km course, from Tanjong Pagar Railway Station to Bukit Timah Railway Station.
After that, they poured the water into a ceremonial well near the finish line.
For every litre that was poured inside, $1 will be donated to Water, a non-profit organisation.
The charity will use the funds to bring clean and safe drinking water to people in developing countries through sustainable water projects.
Captain Steffan Fung, 35, who is a regular commando officer, said that every member of his group carried at least a jerry can containing 20 litres of water and which weighed about 20kg.
He said: "As commandos, we want to make use of our physical fitness and mental endurance to contribute to society.
We come together every Thursday to run and have other forms of physical training."
The men walked together from the starting point at 10am and crossed the finish line about 2 ½ hours later.
"We didn't find the challenge too difficult," said Capt Fung, who has completed four marathons in the past.
The Green Corridor Run was organised by The Nature Society and Groundswell Events.
This article was first published on Mar 9, 2015.
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