The double bridle places two bits in the horse's mouth at once: a bradoon or bridoon (snaffle) and a Weymouth (curb). Each serves a distinct function. The bradoon raises the head and maintains soft, constant contact. The Weymouth engages the poll and chin groove, encouraging the horse to soften into a rounder outline. Used together, they allow the rider to engage the hind leg and lighten the forehand with minute aids.

A double bridle that fits well is a precision tool. One that fits poorly creates confusion, discomfort, and resistance.

A horse does not need two bits to experience curb chain and poll pressure for the first time. A universal with a single mouthpiece, curb strap and two reins teaches those contact areas without introducing a second mouthpiece. A pelham with two reins does the same: the snaffle mouthpiece stays familiar while the chin groove and poll are engaged for the first time.

These setups also teach the rider to manage two reins before adding the complexity of two separate bits.

It's generally best to introduce a new bit set up in a positive environment. The horse should feel calm, secure and preferably doing something they enjoy like a hack. You want to stack the odds in your favour that the horse will associate the new bridle set up with fun rather than hard work.

Use it in conjunction with snaffle and pelham setups through training and keep the association positive. Varying the pressure points keeps the mouth fresh and the horse more receptive to the aids.

When you introduce the double for the first time introduce gradually. First fit the bits and confirm the horse is comfortable at rest. Proceed to walk in hand, lead and halt using the bradoon only. Do not use the curb rein.

If the horse is calm, try to mount up. Contact on the bradoon, very light feel on the curb. Then build over days, not one session. Start with walk, halt, turns, then gradually bring the Weymouth into more active use as the horse settles.

The bradoon sits above the Weymouth mouthpiece in the horse's mouth and is ridden on the snaffle rein. While many regular sized cheekpieces are legal to use as a bradoon, most riders prefer a 55mm ring. It looks neater and is less likely to interfere with the noseband or the Weymouth cheekpieces. Both eggbutt and loose ring bradoons have smaller rings and thinner cheeks than a standard snaffle, so the bradoon and Weymouth can sit together without overcrowding.

Getting the size right is important. The Weymouth is placed below the bradoon so correct size will largely depend on the conformation of the lips at the specific point where the Weymouth sits. For most horses, but not all, the lips tend to get fleshier towards the corners of the mouth.

Bits that are too large shift and interfere with each other inside the mouth. When in doubt, go smaller rather than larger.

Rule of thumb: a loose ring bradoon is typically a quarter of an inch larger than the Weymouth it is paired with. A fixed cheek bradoon (eggbutt) is generally the same size as the Weymouth. This is only a starting point - every horse is unique.

Trapping happens when the two mouthpieces interfere with each other in the mouth. This is more common than most people realise so when introducing the double or modifying the setup it is best practice to always check.

Examine the bits in the mouth both with and without contact on the reins. With contact on both reins, it should be possible to slide a finger between the two bits. If the bits are pressing against each other, the signals become muddled: the snaffle interferes with the Weymouth when the rider intends to give a snaffle aid, and vice versa.

In horses with a shorter smile and canine teeth this can be quite difficult to achieve. Those are the horses which require sometimes quite creative solutions to go in a double. Going thinner on the bradoon, the Weymouth, switching up port sizes or all of the above can make a meaningful difference to correct fit and comfort.

Not all dressage-legal snaffles are legal as bradoons. Rules vary between FEI, national federations, disciplines, and levels, and can change at any point during the year without notice.

• FEI dressage requires a double bridle at Prix St. Georges and above.
• EC dressage permits the double from Medium level upward.
• Mouthpiece thickness rules apply: bradoons typically must be at least 10mm. Check the current rule books for up to date requirements.
• Designs with three or more links are generally not permitted.

Verify the legality of both bits with the relevant governing body every single time before competing.

1. Find the snaffle the horse works best in first, then add the Weymouth.
2. Only change one bit at a time to evaluate the response.
3. The curb chain must be fitted to the 45-degree benchmark.
4. A universal cheek or pelham with two reins is a sound way to introduce curb and poll pressure before adding a second bit.
5. Check that both bits work independently and are not trapping or pressing against each other.
6. Use the double in conjunction with snaffle setups through training. Keep the mouth fresh.
7. Verify competition legality every time.
8. Let the horse tell you the answer.