Firefighters came from all around the Bay Area -- San Mateo, Foster City and Menlo Park, to name a few -- and from as far away as Boston, Mexico and Canada to fill in for firefighters attending the memorial service.
"At least we're able to help," said Foster City Batallion Chief Jim Comisky. "Every one of these individuals volunteered to come up."
Most arrived in San Francisco last night; they received a crash course on San Francisco's unique lay of the land this morning.
When asked what their biggest challenge was in San Francisco, Comisky replied, "Finding out where we're going. It's a bigger city, but we all do the same job."
"This is the Mission District, one of the toughest areas as far as I'm concerned in the nation to ladder," Battalion Chief Kirk Richardson told a group of firefighters. "We have wires. We have narrow streets. We have parked cars. We have buildings set back."
"In San Francisco, the buildings are right on top of each other," said San Francisco Batallion Chief Brendan Ward. "They're wooden. They're like cinder boxes. If we don't attack the fire immediately on the inside of the building, we'll not only lose that building but we might lose the whole block."
Mutual aid firefighters made sure that didn't happen in San Francisco. Under Ward's leadership, a unit responded to a blaze inside a church in the Ocean View neighborhood.
Church Member Ernie Matlock was impressed by the response.
"I'm amazed at how fast they got in and got it out," Matlock said.
Matlock later thanked many of the firefighters on-scene.
Before every briefing on Friday, heartfelt appreciation was heard for the firefighters who came to work today so that hundreds of others could say goodbye to two brothers -- Lt. Vincent Perez and Anthony Valerio -- who will come to work no more.
"The citizens of San Francisco should feel protected, and proud of the men and women of their department, and proud of the California fire service for doing what they're doing," said Assistant Chief Tom Siragusa with the San Francisco Fire Department.
Siragusa made it clear that all San Francisco fire stations were fully staffed and the city was safe and secure. Adapters were provided to outside fire crews to ensure their trucks and engines were compatible with San Francisco's fire hydrants.
During the memorial today, firefighters who were not on-call and could not make the funeral service watched television coverage provided by ABC7 News.