NEW YORK (CNN/Money) - With the arrival of the July 4th holiday, flag companies have been under pressure to distribute their patriotic wares in an industry that has seen huge expansion in the past few years.

"It started with 9/11 and we haven't really seen any letup," said Ryan Halvorsen, general manager of Glen Cove, NY-based Quinn Flags and Banners, noting that sales have jumped 200 percent in three years.

In the week before major U.S. holidays, Halvorsen said sales can jump 500 percent on a week-over-week basis. The company is now processing 150 orders a day and has hired a couple more employees to handle the rush.

This huge volume followed the Sept. 11 attacks and the start of the war in Iraq, he noted.

"There are only a handful of major flag distributors and the past couple years have really made people aware of the growth," Halvorsen continued.

One of the largest orders Quinn Flags saw was a request for 250,000 stick flags from a branch of the U.S. military before the start of the war in Iraq. Leading up to July 4th, patriotic banners and wall fans are popular sellers, according to Halvorsen.

"It just goes to show that people are really behind America," said Tom Jordan, owner of Beaumont, TX-based U.S. Flag and Flagpole Supply Inc., who also said sales at his company have been going strong since Sept. 11.