What Does “Heavy-Duty”
Mean in an Outdoor U.S. Flag
Heavy-duty refers to a flag's ability to take the twin beatings delivered each day by the sun and wind.
With embroidered stars and 13 stripes, the U.S. flag is one of, if not the most, heavily-stitched flags made. That stitching, if done properly, is a source of strength and durability. Poorly done and stitching becomes a source of weakness, especially in terms of fraying and shredding on the fly hem, and the separation of the seams joining the stripes.

Heavy-duty, outdoor U.S. flags are made with either SolarMax nylon or with 2-ply-spun & woven polyester.
SolarMax Nylon from Invista is the most popular flag material in the world, and the default choice for U.S. flags. As the name suggests, SolarMax is designed to withstand the UV effects of the sun.
Polyester: Nylon’s primary weakness is fraying in the fly-hem, especially in larger flags. Spun, woven polyester flags have a more open weave, and are less prone to whipping by the wind.
Polyester flags are generally considered the longest-lasting U.S. flags. If you’ve flown a nylon U.S. flag and it has frayed while still having good color you should consider polyester.

Heavily-Sewn Fly Hem and Seams
Flag should have four to eight rows of stitching on the fly hem, depending on the size of the flag and on whether the maker uses corner hem patches on larger flags.
Annin’s Nyl-Glo and Tough-Tex flags have four rows of lock-stitching on flags up to 6 x 10 ft. Larger flags have six rows of lock-stitching on the fly hem.

Annin flags 15 x 25 ft. and larger also have fly hem corner patches.
Allied Flag Co.’s U.S. flags have four rows of lock-stitching.

Brass Grommets or Rope & Metal Thimbles on Heavy Canvass

  Embroidered or Appliqued Stars