The well-known "never-say-die" spirit of the commandos was cultivated starting from the first generation of full-time national servicemen that enlisted 44 years ago in the elite unit.
"Even though none of us had any idea what the commandos did back then, we still kept our chin up in going through the tough training together," said Mr Teo Chin Tuan, 64, who was among the first batch of NSFs to be posted to the 1st Commando Battalion in 1973.
Out of the 180 who enlisted at the old Changi-Hendon Camp, about 80 completed the nine-month training. More than 60 turned up for a dinner at the National Service Resort and Country Club yesterday to mark the 44th anniversary of their enlistment.
The former servicemen said the tough training and pride in the formation sealed the bond they share.
"It is in our blood - even if we have personal disagreements, I will still trust a fellow commando with my life, " said pioneer Charles Lim, 63, a former corporate officer whose son also became a commando.
The group hold at least four major events a year, including an annual dinner on July 15 to mark their enlistment into national service. More informal sessions, like monthly "makan" sessions, are attended by about 15 people.
General manager Lee Heng Juan, 63, another pioneer, said: "Our friendship is one that was forged through hardship. Like they say, soldiers that suffer together stay together."
Mr Lee, who was the best shot in his sniper course in 1974, added that the daily grind of work in camp helped develop the unit's camaraderie during full-time service.
"We were trained to never leave any man behind. If 30 go out, 30 must return. If anyone falls, we have to carry him," added Mr Lee.
Although the group did not serve their reservist stint as one unit, they started meeting up about six years ago. There are now about 80 members in the WhatsApp chat group.
Mr Lee's nephew, Mr Wong Yang Zhi, 24, was inspired to become a commando.
On his thoughts about the 50th year of national service this year, Mr Teo said: "Today's training might be very different from the past, but the mentality of nationalism, of service to the nation, must remain."