Lions fans hold up "3" signs during Detroit Lions home games to create a raucous atmosphere specifically on third downs when the opposing team is trying to convert. These fans, often seated in designated sections called "3rd Down Town," wave the signs and cheer loudly to distract and pressure the opposing offense, making it harder for them to succeed on these critical plays. This tradition is part of an effort to give the Lions a home-field advantage by encouraging loud, focused fan noise on third downs, which can lead to turnovers or failed conversions. Additionally, this fan ritual is sponsored by Rocket Mortgage, which donates $313 to a local nonprofit called Connect 313 each time the Lions get a third down stop at home. The signs with the number 3 serve both as a rallying symbol for fans and part of a community support initiative. There is also a related trend on social media where Lions fans hold up three different signs to display team spirit, humor, and creativity, expressing their passion and individuality as fans. In summary, the "3" signs at games are about creating noise and distraction on third downs to help the Lions while also involving fans in a spirited and impactful tradition that benefits local causes.