A kimberwicke is bit that can be jointed or have a port. It has separate slots in the bit rings to attach the headstall and reins. The curb chain is attached by the hooks.

A pull on the reins creates a short lever action through the rings themselves to the curb chain, applying pressure in the curb groove under the chin.
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Originated from the American Youth Horse Council's
Horse Industry Handbook
The umbrella organization providing leadership and resources for the youth horse industry.
1-800-TRY-AYHC
