Overcheck

Item of harness over the head of a horse

A bearing rein, also known as an overcheck or a checkrein, is a piece of horse harness that runs from a point on the horse's back, over the head, to a bit. It is used to prevent the horse from lowering its head beyond a fixed point. A variation called a side check passes beside the ears through loops at the top of the bridle cheekpieces.

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