Reinforcements with rubber ring give a slightly softer contact to the horse's mouth. The elastic ring creates a small stretching zone that allows the horse to move forward. Reins are the correct length when the horse's nose bridge is at or near vertical when the nose is level with the nose joint. The freedom of movement of the horse's neck is also limited laterally by tie-ins. These auxiliary reins offer the advantage that the horse is also given lateral support and it cannot easily swerve over the shoulder (a buckling in the neck is avoided) or warp (a crooked position in the gaiters).
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