Gag bit

The gag bit is a type of bit for a horse. With two sets of reins, the gag bit gives a rider the ability to use either a standard direct action or a gag action. In this, the gag bit is related to a Pelham bit and a double bridle. Unlike these, however, the gag bit has no curb strap.

Some styles of gag bit are integral to a special bridle, known as a gag bridle; others are used with a standard bridle. Inside the horse's mouth, the gag bit may be jointed like a snaffle bit or smooth like a Mullen mouth bit.

The gag bit works on the horse's lips and poll simultaneously. The pressure on the lips tends to make the horse raise its head, which is useful for a horse that tends to lean on the bit. Gag bits are used mainly for horses that are strong pullers or for horses that need retraining. Gag bits are most commonly seen in polo, eventing (especially for cross-country), show jumping, and hacking, mainly for increased control at times where a horse may be excited or try to run off with the rider.

They can also be used to help elevate a horse that is heavy on its front end.

They are not permitted at any level of dressage, since dressage riders are trying to get the horse to come down onto the bit, and want to encourage the horse to accept contact. Additionally, the horse is supposed to be completely submissive in dressage, and a gag bit gives the impression that it is not. Gags are also never seen in the hunter arena, again because riders wish to portray that the horse is an easy ride, and because the ideal is a long, relaxed frame with the neck stretched out, rather than a high neck.

Gag bits are also occasionally seen in western-style competition, usually in the form of a sliding mouthpiece on a shanked curb-style bit (similar to the American gag).

The gag bit normally is used with two sets of reins; one on the bit ring that does not apply gag leverage, and the other on the small ring attached to the cord or rolled leather strap of the gag bridle cheekpiece. This allows for the bit to be used as a normal snaffle, with gag action used only when needed. Polo players, who must ride with the reins in one hand and cannot make instant fine adjustments, often use a gag bit with draw reins.

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