This bevel bit allows mild leverage. A copper lozenge assists with salivation. Mouthpiece thickness: 16mm. Cheek height: 55mm (4.5", 5"), 70mm (5.25", 5.5", 6"). Stainless steel is the most common material for bits. Durable, easy to clean, tasteless and does not rust. Copper is used in the mouthpiece, creating warmth and encouraging salivation to keep the mouth soft.