There is a direct relationship between U.S. campaign streamers and the medal that a campaign represents. The streamer represents the unit's participation in a campaign and the medal represents an individual's participation in that campaign (U.S. Army – some differences for the U.S. Navy). When a campaign is established, participating unit's are authorized a streamer and each service member assigned to the unit during that same time is authorized the medal. Sometimes these medals are campaign medals, other times they are service medals, but that streamer/medal relationship normally remains. Units in the U.S. Army that trace their heritage and lineage to the Civil War are entitled to display a battle streamer for the Civil War on their flagpoles. This streamer is half blue and half gray, the color theme of the second ribbon design. Units with Confederate lineage use campaign streamers with the gray edge up and units with Union lineage use campaign streamers with the blue edge up. The campaign lettering requires two distinct sets of streamers for each campaign, one set for each side.