A cup-shaped device applied over the sides of the horse's head near his eyes to limit his vision. This helps to prevent him from swerving away from distracting objects or other horses on either side of him. Blinker cups come in a variety of sizes and shapes to allow as little or as much vision as the trainer feels is appropriate.
shields attached to the bridle to inhibit the horse's peripheral vision. Originally used so that the carriage horse would not be frightened by the sight of the carriage close behind it
Flaps on the bridle that keep a horse from seeing to the side or back.