Sweet iron and copper encourages salivation and produces a pleasant taste in the horse's mouth. Raised copper ribs can help to prevent the horse taking too much of a hold. Three rings offer leverage options to increase severity. The 5" and smaller sizes come with shorter cheeks to ensure the bit remains in proportion with the smaller head. Mouthpiece thickness: 16mm. Cheek height: 145mm (4.5", 5"), 180mm (5.5"). Sweet iron mouthpieces are designed to oxidize to produce a sweet taste which helps with mouthing. The addition of copper to the mouth ensures the horse will not take up too much of a contact, ideal for horses that can take a hold. Stainless steel is used for the cheeks due to it being durable, easy to clean and resistance to rust.