The medium port is not only a good everyay working bit, it is also  a gentle but effective tool when you need to advance the horses ability to give his chin and frame his body.  The lighter weight Aluminum shanks enhance performance.  The mouth is designed to rust and creates a "sweet" or pleasing taste that horses enjoy.

Shanks: 8 1/2" Aluminum with brass spots.

Mouth: 5" "Sweet-Iron" medium port with copper inlay.