What is a double bridle?

The USEF Dressage rule book words it this way: a double bridle has bridoon and curb bits each attached to a separate rein, the curb bit must have a curb chain, and a cavesson noseband is the only noseband permitted with it. (USEF spells it 'bridoon'; most riders and makers say 'bradoon.' They are the same bit.)

The bradoon is a small snaffle. The curb, usually called a Weymouth, has shanks that extend below the mouthpiece and a chain that lies in the chin groove. Herm Sprenger describes the split of jobs like this: the bradoon carries the main rein aids and acts like a normal snaffle, while the Weymouth, used with the curb rein, refines the aids, and its shanks rotate around the mouthpiece to create leverage and poll pressure.

A double bridle looks like a lot of leather, but it is a set of parts with separate jobs. Learn the parts and the rest follows.

USEF defines it as a non-leverage bit with the rein attached at the level of the mouthpiece. For dressage, USEF allows a loose ring or an eggbutt cheek on a bradoon, and prohibits D rings, full cheeks, half cheeks and hanging cheeks there. The mouthpiece must be at least 10 mm where it meets the rings, with one or two joints. Our loose ring, eggbutt or D-ring page explains what each cheek does.

On fit, Herm Sprenger's advice is to choose a bradoon with the same width and shape as the snaffle your horse normally wears, and to fit it in the same place as a normal snaffle, not higher.

That is the definition in USEF's DR121. When the rider takes up the curb rein, the shank rotates and the curb chain comes into play. A University of Florida extension specialist, Dr. E. L. Johnson, writes that a longer shank produces more leverage than a shorter one, and that a straight shank is quicker acting than a curved one. A University of Georgia extension bulletin says a tighter curb strap means less pressure on the poll.

Herm Sprenger describes the curb chain as the part that limits poll pressure, and says ideally it engages when the angle between the lower shank and the mouth is 30 to 45 degrees. It says common lower shank lengths are 5 cm and 7 cm, and that a shorter 'baby' Weymouth reacts faster but gives less poll leverage. USEF dressage rules set limits too, shown in the table.

Shopping note: some makers sell the chain separately. Nathe, for example, notes that its Weymouths come without a curb chain; see our Nathe page.

Herm Sprenger says the bradoon takes the main aids and the Weymouth refines them. Anita Marchesani, a bitting specialist interviewed by Horse Nation in 2012, says leverage bits generally ask for head lowering, and that a Weymouth in a double bridle refines head carriage and collection. Wikipedia notes that double bridles were once the standard for trained riders, and that modern riders usually ride mainly on the bradoon.

Notice what none of these sources says: that the hardware does the work. The University of Florida bulletin puts it plainly: whichever bit is chosen, what 'generally makes it good or bad are the hands using it.' The University of Georgia bulletin makes the same point, and adds that a horse should already accept bit pressure, and that too much poll pressure too early in training can make a horse fight or evade.

DR121 says the double bridle is permitted only at Third Level and above. The table below is the rule book's Figure 121.11 for tests ridden under national rules.

Herm Sprenger, a German maker, writes that the double bridle is compulsory in most competitions from medium level up in Germany; USEF's table for the US is the one above. The rules differ in FEI competition, so check the current FEI Dressage Rules for those events. There's also a rule that matters at home: the USEF rule on lungeing says a double bridle may not be worn while lungeing.

Dressage isn't the only place. In USEF hunter classes, rule HU105 lists snaffles, pelhams and full bridles, all with cavesson nosebands, as the required bridles; 'full bridle' is the hunter-ring name for a double bridle. Wikipedia adds that the double bridle is also seen in show hack classes and in US saddle seat, though it has largely given way to the snaffle among US show hunters. For other disciplines and organizations, read the rule book for your division.

This is the part to do with a trainer or a qualified bit fitter. Herm Sprenger's fitting article, summarized in the list below, is the source for most of the numbers here. Sprenger also says to consult a specialist dealer or the manufacturer when in doubt.

Two things come from the rule book, not the maker. DR121 sets a minimum thickness of 10 mm for a bradoon and 12 mm for a curb in USEF dressage, and Sprenger's thicknesses sit above those figures. For measuring the width of a bit, see What size bit does my horse need?

• Width: use a bradoon of the same width and shape as his usual snaffle. Herm Sprenger says to choose the Weymouth 0.5 to 1 cm narrower, since it sits lower, where the mouth is narrower. It also says the idea that the Weymouth must be bigger than the bradoon is misleading and tends to lead to bits fitted too big and too high.
• Sides: they should sit close to the corners of the mouth without pinching.
• Thickness: Herm Sprenger says small mouths should have no bit thicker than 16 mm, and gives 14 mm for the bradoon and 16 mm for the Weymouth as the German average, with 14 mm for a delicate mouth.
• Height: it says to leave at least one to two fingers between the mouthpiece and the first lower molar, and the two bits must not touch each other when the reins are taken up.
• Chain: hook it into the chain hooks with the links flat against the lower jaw, engaging at 30 to 45 degrees.

USEF's DR121 points to Annex A for additional information on permitted and prohibited bits, and that Annex lists specific models. Our Is this bit legal for dressage? page walks through how to look a bit up, and what changed in 2026.

If you're coming from a snaffle, ask your trainer before you buy. If the horse fusses at the bit, have his teeth and mouth checked by a vet or equine dentist rather than changing bits again.