The jointed bevel bit allows mild leverage and offers a little more control, promoting outline, head carriage and responsiveness. The sweet iron encourages salivation. Mouthpiece thickness: 14mm. Cheek height: 55mm (4.5, 5), 70mm (5.5). Sweet iron mouthpieces are designed to oxidize to produce a sweet taste which helps with mouthing. Stainless steel is used for the cheeks due to it being durable, easy to clean and resistance to rust.