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Happy Mouth Mullen Mouth King Dee

Happy Mouth
- Item #14989
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As riders and online shoppers, we know it can be tough to buy a new bridle or pair of boots without trying them on. That's why we moved the fitting room to your living room (or barn)! From breeches to blankets, if you or your horse can try it on, you can return it, free! Just use the pre-paid return label included in your order within 60 days from the purchase date. And of course, please make sure the item is in like-new condition with original packaging (we said 'fitting room', not 'war room'!).

Why We Love This

A favorite with top trainers, Happy Mouth bits are covered with a soft, flexible, yet extremely durable, apple-scented plastic which encourages acceptance and softness. The Happy Mouth Mullen Mouth King Dee has an inner core of twisted wire for more flexibility. All cheeks are stainless steel. 5", 5 1/2", 5 3/4". 20mm thickness.


Available in  5", 5 1/2", 5 3/4"

What Customers Say:
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    "Happy Mouth bits are uniquely constructed with high ...
    "Happy Mouth bits are uniquely constructed with high tech plastics, making them soft, flexible, gentle and comfortable for your horse. The unique apple scent increases your horse's acceptance. Happy Mouth bits are non-toxic, flexible and long lasting with a stainless ...
    "The Korsteel Corkscrew Hunter Dee is made of ...
    "The Korsteel Corkscrew Hunter Dee is made of high quality polished stainless steel. The corkscrew mouthpiece helps the rider to control and slow a more forward horse. Imported"
    "Korsteel bits are proven performers for all levels ...
    "Korsteel bits are proven performers for all levels of training and competition. They are crafted from materials of the highest quality. 15mm thick. Imported."
    "The JP Hunter Dee w/ Dr. Bristol has ...
    "The JP Hunter Dee w/ Dr. Bristol has attractive Dee rings and comfortable curved bars. The Dr. Bristol link applies tongue pressure when required by rider. Imported."
    "Happy Mouth bits are uniquely constructed with high ...
    "Happy Mouth bits are uniquely constructed with high tech plastics, making them soft, flexible, gentle and comfortable for your horse. The unique apple scent increase your horse's acceptance."
    "The Myler Bitting System is a graduated system, ...
    "The Myler Bitting System is a graduated system, meaning that as your horse learns and progresses through his training, you will change the way you communicate with him by re-bitting him periodically. Each Myler Bit is designed to use select ...
    "Happy Mouth - The Art of Gentle Persuasion! ...
    "Happy Mouth - The Art of Gentle Persuasion! New Fun Colors for Spring! Same Great Apple Scented Mouthpiece -- The long wearing apple scented are now available in 3 fun pastel colors. Not just for ponies... fashion conscious horses will ...


    out of 5
    92% of customers would recommend this product to a friend!
    Tell us what you think!

    SmartPak customers are some of the most conscientious animal owners around. We encourage you to share your experience with the products we sell to help fellow customers to make informed choices for their animals. We do not edit these reviews in any way - they are direct customer-to-customer communication. We do monitor reviews for positive and negative feedback, and use this feedback to improve our selection as well as sharing feedback with product manufacturers to help them improve their products. Please note that we recommend consulting your vet with serious health issues.

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    Happy Mouth Mullen Mouth King Dee is rated 4.5 out of 5 by 24.
    Rated 5 out of 5 by from Best bit ever I used this bit on all my jumper horses - and they are very energetic and sometimes very strong. That said, the bit always works great and the all love it..
    Date published: 2015-06-06
    Rated 5 out of 5 by from Horse Loves It My horse has been using this bit for years. I bought another one of these for his new show bridle because he loves this bit. He has a sensitive mouth, but takes this bit with ease.
    Date published: 2015-04-16
    Rated 5 out of 5 by from Good Results My gelding has responded very well to this bit. I made the change two weeks ago. Heis now working with a softer more responsive mouth.
    Date published: 2014-03-18
    Rated 5 out of 5 by from Really Nice I really like this bit, o stared a young, EXTREAMLY sensitive horse over fences and she did really well! a plain snaffle was still to much for her, we tried this and it immediately made a difference.
    Date published: 2013-12-05
    Rated 4 out of 5 by from Great bit! Wears down quickly, though... This bit is very nice. I love the Dee ring for showing and my horse loves the gentle and chewy rubber! Unfortunately, he loves it a little TOO much, haha! He has chewed through 5 of these in the last year! I'm disappointed on durability (but maybe it's just my horse that has a chewing habit...) but he works well in the bit so we're keeping him in it. I think we're going to try wrapping it in latex (which I'm sad to see SmartPak doesn't offer!). All in all, great bit, just a little disappointed about durability. But, I understand that's what you get for having a rubber bit!
    Date published: 2013-08-14
    Rated 5 out of 5 by from Great bit for a young horse! Want my green hunter to reach down into the bit more, this bit is awesome!!! Noticed a difference the first ride!
    Date published: 2013-05-14
    Rated 4 out of 5 by from Soft and Simple Communication I love the fact that it is a very mild bit with no joints or moving ring parts. My mare seems to have a very sensitive mouth and I needed something that would provide soft and simple communication.
    Date published: 2013-02-26
    Rated 5 out of 5 by from Training made easy I recently purchased one of these for myself, because at my barn we only have one, and almost all the new, uneasy horses, as well as some of the laid back horses, all need to use it. The bit was used two or three times a day, and had stayed in incredible shape and pretty clean, considering how much it is used. An added bonus is that the reins don't work their way to the straight part of the dee ring like it can with most other dee rings. This is a great training aid and incredibly durable!
    Date published: 2012-06-09
    Rated 5 out of 5 by from Really great bit! Awesome for sensitive mouths. Makes my horse happy!
    Date published: 2012-05-03
    Rated 4 out of 5 by from Mullen Mouth Sizing Strange I ordered the 5.75 mullen mouth and it came and was HUGE, so I sent it back (great customer service on my return!!!) and got the 5.5. IT was huge too!! I just didn't have the heart (or cash) to send it back again, so someone at my barn bought it. It was a nice looking bit, but careful with sizes!!
    Date published: 2011-06-03
    Rated 5 out of 5 by from Cherokee loves this bit My horse hated every bit but he thinks this one is great
    Date published: 2011-04-21
    Rated 5 out of 5 by from Nice option for a bit sour horse My new draft rescue would run when she saw me carrying a metal bit. After several days of desensitization, she took the Happy Mouth bit. Her eyes softened and her face visibly relaxed. That said, I wish there was more of a curve to accommodate the tongue. But we'll be sticking with Happy Mouth products when we move to a French link snaffle.
    Date published: 2010-09-13
    Rated 4 out of 5 by from Good for hard mouths I bought this for my warmblood who has a hard time feeling "secure" in a snaffle bridle and pulls on my hands to remain in contact when not in his double bridle. With this bit, I felt that he wanted to stay on the aids more and felt more confident with our connection. It is by no means an aggressive or harsh bit, but seems to be effective in keeping him on the aids.
    Date published: 2010-07-05
    Rated 4 out of 5 by from Good training bit I really like the Happy Mouth bits for sensitive mouthed horses or for starting babies. I know I'm not hurting their mouths and I have a great contact and good connection with this bit. I don't like how it wears down though. Plastic pieces start coming off of the bit after heavy use. And I definitely wouldn't recommend it for a horse that chews the bit, it won't last at all. Aside from that it is a good training or transition bit.
    Date published: 2010-04-30
    Rated 5 out of 5 by from Amazing
    Date published: 2010-02-05
    Rated 5 out of 5 by from Comfort Bit This is a nice easy and comfortable bit. Our horses accept it willingly without any complaint. I use this bit for pleasure riding on well trained horses but have not tried it for training or advanced work where a more defined contact is required.I would suggest it as a good old reliable piece of equipment to keep handy.
    Date published: 2009-08-31
    Rated 5 out of 5 by from I'll never go back to a metal bit! I can't believe how much happier my horse is in this bit. He is much less mouthy and seems to really relax into a contact. His reaction has made me a total believer in the Happy Mouth bits!
    Date published: 2009-07-29
    Rated 5 out of 5 by from
    Date published: 2009-07-23
    Rated 5 out of 5 by from Finally, a bit she likes After starting my young horse in a mullen mouth driving bit I could not get her to accept a snaffle for riding - even a good Sprenger bit! She loves this bit though and has stopped grinding her teeth and is now a happy riding - and driving - horse. These are definitely Happy Mouth bits.
    Date published: 2009-06-23
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