Used 5″ Myler (MB33, Level 3) flat shank curb. This mouthpiece is made of polished sweet iron which naturally oxidizes or rusts. Harmless to horses, it has a sweet taste and promotes salivation. (MB33, Level 3) Stainless steel 8″ flat shank with sweet iron ported barrel, copper inlay 5″ mouth. The mouth has rusted, which does offer a sweet taste. In good used condition. Offers good tongue relief.