why does brian branch have a green thing on his helmet

Brian Branch has a green mouthpiece stuck in one of the holes of his helmet, which he has been doing since college. He puts the mouthpiece on his helmet because he finds it difficult to breathe with it in his mouth during plays. The green mouthpiece has personal significance to him, though he hasn't shared the details. It essentially serves as a personal trademark or good luck charm, though he doesn't wear it regularly during all plays. Sometimes he uses it when expecting a heavy hitting game. The green mouthpiece has become a distinctive part of his on-field look and identity.