The Bait Flag prevents the hook, which has been pierced through the baitfish, from falling out. You can also use the Bait Flags as a visual lure. Many anglers believe—not just when spin fishing—that visible, colored spots on the bait can entice predatory fish to bite. The red color was deliberately chosen for the Bait Flags. Underwater, fish tend to perceive red as a natural brown tone. Nevertheless, this color provides enough contrast to the baitfish to serve as a target point.