Serving D.C. police officers has long been tradition at Mangialardo and Sons. It was the local beat patrol, in fact, that persuaded the owner of the Italian grocery on Pennsylvania Avenue SE to start assembling his meat, cheese and hard rolls into sandwiches in the late 1960s.

Since then, the city and police department have gone through many changes. But the Mangialardo family still brings 'em in: The store is often full of police officers, firefighters and FBI agents. The family estimates that it serves 40 to 50 police officers a day, plus about the same number of firefighters and federal agents.

"I think [it's] because we give them a good sandwich, and we're nice to everybody," said Joe Mangialardo. His wife, Lucille, and sons, Tony and Alex, also work at the store, which was founded in the 1950s by Joe's parents, Antonio and Anna.

The deli doesn't advertise much and doesn't spend much on decor: The narrow storefront is packed with coolers and pallets stacked with soft drinks, leaving only a small space for customers to stand while waiting for their orders from the sandwich counter.

The attraction is the food, especially the "G-man" sandwich, which includes ham, salami, mortadella and pepperoni, plus provolone and fontina cheeses. The G-man was created decades ago by Joe Mangialardo, when he prepared sandwiches for two FBI agents heading to a Washington Redskins game.

Soon after, "Some agents came in and said, 'We want a couple of G-men,' " said Tony Mangialardo. The new sandwich had a name. And some customers have been ordering the calorie-buster for 30 years.

Among police, the place has become famous for the food, the cheap prices -- the G-man goes for $4.95 and is big enough to choke a horse -- and the friendly banter of the Mangialardos, who take orders and staff the front counter.

"They told me about Mangialardo's when I was in the academy" in the late 1960s, said Gary Hankins, a consultant for the Fraternal Order of Police who is also a former D.C. officer. "They were just friendly, good folks that did for their neighbors, and did for the police."

The location might not look like much. The store is set in the worn 1300 block of Pennsylvania. Joe Mangialardo estimates that only about 2 percent of the deli's customers come from the neighborhood.

But for many police officers, the spot is ideal. It is on the way from Southeast Washington to police headquarters, and on the way to the city jail for suburban police. Officers from Maryland and Virginia often stop by on their way to interview D.C. prisoners, the Mangialardos said.

The location is also convenient for officers whose home beats are in tough neighborhoods, where the only restaurants are greasy carryouts whose clerks work behind bullet-resistant Plexiglas. One such fan is 7th District officer Cliff Weaver, who stopped in for a Mangialardo's turkey sandwich on his way to work Friday.

Weaver said he chooses turkey because it is lighter than, say, the G-man sandwich, in case he needs to chase after someone later in the day.

Although many officers know the restaurant, there is considerable disagreement over what it is called. Many mangle the long Sicilian name, or shorten it to something like "Mag's."

As it turns out, the pronunciation is a topic of debate even within the Mangialardo family. Tony said he pronounces it with a hard g: "Mang-a-lar-do's." Brother Alex prefers the more authentic Italian pronunciation, with a soft g: "Manj-a-lar-do's."

"We always say, as long as you come in, you can call us whatever you want," Tony Mangialardo said.