Pro Professional Mullen Barrel Dee Bit

A Dee Ring bit (also called a "D-ring snaffle") is a fixed-cheek bit named for the D-shaped rings on either side of the mouthpiece.

Design

• The rings are shaped like the letter "D," with the flat side of the D running vertically alongside the horse's mouth and face.
• The Dee rings are attached to the mouthpiece, while the reins and cheekpieces both typically attach to the same ring (unlike the Baucher or Full Cheek, which separate these attachment points).
• The flat side of the D lies against the horse's cheek, offering a moderate level of lateral support — less rigid and less protrusive than a Full Cheek's long bars, but more stable than a fully round loose-ring.
• Because the rings are fixed to the mouthpiece, the bit lays still in the mouth and doesn't slide side to side, unlike a loose-ring design.

Function

• Steady rein contact: Because the rings are attached directly to the mouthpiece, rein contact stays more still towards the mouth, creating a stable feeling for both horse and rider.
• Encourages consistent contact: This stillness encourages the horse to keep a steady contact towards the bit, rather than the mouthpiece shifting and unsettling the feel.
• Moderate steering support: The straight, flat sides of the Dee Ring press against the horse's face during a turn, giving a mild version of the same lateral guidance a Full Cheek offers — helping with steering and framing without the length (or snagging risk) of full cheek bars.
• Reduced pinching: Because the ring doesn't rotate as freely as a loose-ring, there's less risk of the mouthpiece pinching or rubbing the corners of the lips.
• Stability without bulk: The D-ring offers a "middle ground" of stability — more settled in the mouth than a loose-ring, but without the visual bulk or protruding bars of a Full Cheek. This makes it a popular, low-fuss option across many disciplines.
• No leverage/poll pressure: Like other fixed-ring or shanked-but-unattached-to-curb designs, the D-ring has no lower shank or curb chain, so it functions purely as a direct-pressure snaffle with no leverage action on the poll.

What it's good for

• Horses that need some steering support but don't require a Full Cheek: A good "step down" in lateral assistance — useful for horses that are fairly straight but occasionally need a little extra guidance in turns.
• Horses transitioning from a loose-ring to more stability: Because it doesn't have moving cheek pieces, it offers a steadier feel that can suit horses learning to accept a more consistent contact.
• Young or green horses: Similar to the Full Cheek, it's a common early bit choice because of its clear turning cues, but without the snagging risk of the longer cheek bars (so no bit keepers are usually needed).
• Disciplines like racing and polo: The Dee Ring is a traditional choice in these sports because it provides directional cues without protruding parts that could catch on equipment or other horses during close contact.
• Riders wanting a simple, all-purpose option: It's widely regarded as a versatile, comfortable, low-maintenance bit suited to a broad range of horses and levels.

Competition legality

The Dee Ring is widely accepted across disciplines, including FEI-approved for dressage, much like the Full Cheek and Baucher.

Summary

The Dee Ring bit offers a moderate middle ground between the free movement of a loose-ring snaffle and the fixed stability of a Full Cheek — giving steady contact, some steering support, and mouth stability with minimal bulk or snagging risk, making it a popular all-around choice, especially for young horses, and in disciplines like racing and polo.

This describes a Myler-style "Mullen Barrel" mouthpiece — a clever hybrid that gives the mullen mouth's traditionally solid, joint-free profile some genuine flexibility and independent movement through a rotating central barrel, built in stainless steel with copper worked into the tongue-contact surfaces for taste and acceptance.

Design

• Unlike a true mullen mouth (a completely solid, non-jointed bar), a mullen barrel has a rotating barrel or bushing at the center of the mouthpiece, which allows the mouthpiece bars to move somewhat independently of each other — while still relaxing into a smooth, curved, mullen-like shape when the bit isn't under pressure.
• This barrel makes the mouthpiece double jointed in a mechanical sense, but designed to curve closed rather than scissor closed, unlike a standard single- or double-jointed bit — there's no sharp folding action at all.
• Copper inlay is worked into the tongue-contact surfaces of the mouthpiece (rather than the whole bar being copper), giving a taste benefit specifically where the tongue meets the bit.
• Made primarily of stainless steel, with the copper limited to the inlaid sections.

Function

• Relaxes into a mullen shape at rest, curves smoothly under pressure: When the reins are slack, the barrel allows the bars some freedom of movement. When the reins are engaged, the mouthpiece straightens into something like a solid bar, but with an exaggerated curve rather than a flat straight bar — this curved bar then rotates across the bars and lips, settling down onto the tongue.
• No risk of poking the palate: Because the barrel's action curves closed smoothly rather than scissoring at a sharp angle (as a standard single joint does), there's essentially no chance of the center of the mouthpiece jabbing up into the roof of the mouth, even if the horse's head position or the rider's hand angle would otherwise create that risk with a conventional jointed bit.
• Independent side movement: The barrel allows each side of the mouthpiece to rotate somewhat independently, letting a rider isolate one side of the bit for bending, balancing, or lifting a shoulder — a more precise, one-sided signal than a fully rigid mullen can offer.
• Allows the tongue to elevate and swallow more easily: Because the mouthpiece isn't a single rigid bar, the tongue has some room to move under it, which some horses — especially those recovering from mouth trauma or that resist a completely fixed mouthpiece — find considerably more comfortable.
• Encourages salivation via copper inlay: The copper worked into the tongue-contact areas has a naturally sweet taste, encouraging the horse to salivate and relax the jaw, similar to the effect of any copper-inlaid mouthpiece.
• Mild lifting action: Some versions of this mouthpiece produce a gentle lifting effect at the bars and lips when engaged, which can serve as a reminder for horses that tend to drop a shoulder or move crookedly — though this works best alongside genuine training exercises, not as a standalone fix.

What it's good for

• Horses recovering from mouth trauma or damage: The flexible, forgiving nature of this mouthpiece — with no sharp joint action and no risk of palate contact — makes it a comfortable choice for horses with a sensitive or previously injured mouth.
• Horses that tend to fall behind the bit: The curved, non-scissoring action gives these horses a stable, encouraging mouthpiece to move into, rather than one that folds sharply and might provoke further evasion.
• Young horses and retraining prospects: The overall comfort and mildness, combined with a clear but gentle lifting reminder, make this bit well suited to youngsters or horses being reschooled after previous negative bit experiences.
• Horses that move crookedly or drop a shoulder: The independent side movement lets a rider isolate one side for more precise correctional cues, useful alongside dedicated straightness work.
• Riders wanting more nuanced communication than a fixed mullen offers, without moving to a jointed bit: A good middle ground between the total rigidity of a plain mullen and the folding action of a standard jointed mouthpiece.

A note on fit and inspection

The mouthpiece bars narrow at the point where they enter the barrel before widening again inside it — this transition point is worth periodically inspecting, as it represents one of the mouthpiece's structurally thinner areas, though it's generally not considered a pinch risk to the tongue.

A note on classification

• The overall lateral action still depends on the cheek style (loose-ring, D-ring, shanked, etc.) this mouthpiece is built into — some versions add genuine leverage via a shank, while others remain on a plain snaffle-style cheek.
• This mouthpiece is not legal in all show circles, so it's worth checking the rules for the specific discipline before use in competition, though certain versions with low, compliant ports are built to meet USEF/FEI dressage requirements.

Summary

A Mullen Barrel Stainless Steel bit with Copper Inlay offers the comfort and mildness of a mullen mouth combined with genuine flexibility and independent side movement through a rotating central barrel — curving smoothly rather than folding sharply, with no risk of palate contact, and copper inlay to encourage salivation and acceptance — making it an especially forgiving, comfortable option for young horses, retraining prospects, or horses with a sensitive or previously injured mouth, while still offering the rider clear, precise, one-sided communication when needed.