This Dutch gag has a Waterford mouth made of many different links which makes it hard for the horse to take hold of and pull against it. The gag cheeks add leverage. This can be a very severe bit and should be used with care. The 5" and smaller sizes of this bit come with shorter cheeks to ensure the bit remains in proportion with the smaller head. Mouthpiece thickness: 18mm. Cheek height: 150mm (4.5", 5"), 180mm (5.5", 6"). Stainless steel is the most common material for bits. Durable, easy to clean, tasteless and does not rust.