El Salvador Outdoor Nylon Flag 3'x5' Adopted on May 27th, 1912, the El Salvador flag is a horizontal triband of blue (top and bottom) and white in the center. All nylon flags are finished with a strong, durable snow-white header and brass grommets. Expertly crafted using 100% heavyweight, 200-denier nylon bunting, and treated to resist sun and chemical deterioration..