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One K Defender Matte Helmet

One K
- Item #21807
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We're bringing you this product at the lowest price allowed by the manufacturer. That means this item isn't eligible for additional discounts or promotions.

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

The One K Defender Matte Helmet is sure to keep you cool with two side, two front, one back, and two center stripe vents! This all-around stylish helmet is great for both schooling and showing in a number of different disciplines!

Favorite Features

  • Polycarbonate and Advanced ABS Composite outer shell with an injection molded shell design
  • Inner lining is anti-microbial, moisture wicking, quick drying, and washable
  • Stainless steel mesh
  • Comfort padded harness with synthetic suede lining and Fastex buckle


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    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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    One K Defender Matte Helmet is rated 4.7419 out of 5 by 31.
    Rated 5 out of 5 by from Great helmet! I just purchased this helmet a few weeks ago, and I love it! Beautiful quality. It is very lightweight which I really like. It seems very durable but I haven't had it long so I can't say for sure. I have an especially large head so it was important for me to have a low-profile design, and this helmet really has that which I appreciate. This helmet definitely runs small, be sure to size up if you are in between sizes.
    Date published: 2014-12-24
    Rated 5 out of 5 by from So pleased with this helmet! I am so glad I made the decision to buy this helmet after much research. Nicely padded and comfortable.
    Date published: 2014-12-23
    Rated 4 out of 5 by from Brilliant for everyday riding, comfortable! I bought this after I tried the Charles Owen Ayr8, and I much prefer the feel of this helmet. I wanted something primarily for schooling that would still look fine for showing. This is a fantastic helmet for everyday riding and still has some style. The removable liner is simply perfect and so smart! I also love the ventilation as I can actually feel a breeze through them. For the fit, I definitely have an oval shape but this helmet fits very well. My one complaint is the chin strap as it is pretty bulky and rests pretty far forward. I have a petite face so the straps are a bit overwhelming. Overall, I am very happy with my decision when I picked out this helmet.
    Date published: 2014-11-24
    Rated 5 out of 5 by from In LOVE I purchased this helmet after I got a concussion in my old helmet. I liked the look of samsheilds but not the price so I decided to go with this helmet... and boy am I glad I did!! This helmet is goregeous! It fits like a glove! Did I mention the padding? Just Like a Pillow! I am so happy with this purchase!!
    Date published: 2014-11-05
    Rated 4 out of 5 by from Very Comfortable, makes wearing a helmet enjoyable Only have had it about a month and I am still in love. It slips right on and feels secure. The vents make riding in the heat much nicer, you can feel the air moving through the helmet! The only thing that could improve is possibly the chin strap. It is comfortable and I am more than use to it now but it is much different than the Charles Owen, which is what I'm used to. It's a great helmet for schooling and might even pass it off as a show helmet it is very classic.
    Date published: 2014-10-31
    Rated 4 out of 5 by from The only helmet that fit! My 5 years were up on my last helmet, and it was time to get a one. To my dismay, most of the helmets made today did not fit my large (~7.5") head. The sales girl at the Natick store was very patient. This was the closest to a good fit that I could find. No pressure points. The harness is a little uncomfortable as it is plastic, and tho the helmet itself just fits, the harness is too big and can't be tightened as much as I would like. But there was no better option. I am concerned that the harness may not last 5 years - but time will tell. For the price, I would have expected a leather harness.I can't believe that helmet manufacturers don't make anything larger than a 7 3/8 helmet!
    Date published: 2014-10-16
    Rated 5 out of 5 by from Great helmet for the money I purchased this helmet for my daughter when she suddenly needed a replacement due to a harness failure on another brand helmet. I knew the One-K would fit her head shape as she had tried one on belonging to another rider at our barn. This helmet is well designed and well made. While I was worried at first about the discrete sizing, the nature of the One-K liner and the material it's made from made for a perfect fit. I also like the velcro adjustment on the chance of the end of the strap blowing in the wind. Overall, I'm very impressed and would consider this helmet again for future purchases.
    Date published: 2014-09-25
    Rated 4 out of 5 by from comfortable and amazing look my daughter bought this helmet and it's super lightweight and comfortable! definitely easy on the wallet compared to other helmets like this, but still great quality. my daughter loves the look of it too!
    Date published: 2014-08-26
    Rated 5 out of 5 by from I have been wearing this helmet for 2 weeks now and I like the fit. The under chin strap I find a bit too forward but I tend to think that this is the correct place for it.
    Date published: 2014-08-11
    Rated 5 out of 5 by from Easy ordering great customers service quick ship Bought the 1k helmet & my daughter loves it. It's very hot were we live and this helmet let's her head breath
    Date published: 2014-08-05
    Rated 4 out of 5 by from Fits like a glove! Was hesitant on ordering a helmet online, but on sale and took a chance. Followed the fit guide and the helmet fits perfectly, no adjustments needed. Doesn't wobble, and so far in summer riding it keeps my head cool. Only issue I hope works itself out a bit are the chin straps - they're a bit stiff so maybe after some more wear they'll break in.
    Date published: 2014-08-05
    Rated 5 out of 5 by from Very Comfortable This is my second One K helmet. They are so comfortable that I decided to toss my old brand and have a spare!
    Date published: 2014-08-05
    Rated 5 out of 5 by from Beautiful helmet! This is a lovely, classy helmet. Whether you are an eventer, dressage rider, or H/J this helmet is flattering and professional looking. Love the fit too!
    Date published: 2014-08-04
    Rated 5 out of 5 by from Fabulous helmet! After several years in an IRH with a chinstrap that would slip occasionally, I decided to upgrade. I originally purchased an IRH Air but it looked too big on my head, so back it went (Thanks Smartpak for the easy return!). I exchanged it for the OneK Defender, and I am so glad I did. It looks great (low profile) and is so comfortable. I showed in it last weekend and in the hot weather, I could feel the air moving through the top of the helmet. Worth every penny.
    Date published: 2014-07-22
    Rated 5 out of 5 by from A- helmet, great price! I've had my CO ayr8 for longer than i should probably admit, and I have never found another brand that fit. It's pretty flattering and classy for the price and the vents seem like they'll work even better than the ayr8. My only complaint so far is that it's hard to get on when you're putting your hair up because the velcro that holds the front of the liner in slides back. I'm sure there's another trick to it, so overall great helmet for the price! I'm a 7 3/8 and I bought the xl, which fits ALMOST as well as my CO with my hair up and even better with it down. I might still be showing the the ayr8 because it's more classic, but these are great and gaining popularity pretty fast!
    Date published: 2014-07-15
    Rated 5 out of 5 by from LOVE I bought this helmet to replace my IRH. What a difference. It is lightweight, fits great and doesn't give "bubble head." I love the venting, since it stays fairly warm year round in California. It's easy to clean and the removable liner is great. I used to break out on my forehead from my helmet, but being able to wash the liner has made a huge difference. The price point seals the deal for me. I've had the helmet for 2 years and it still looks brand new.
    Date published: 2014-07-15
    Rated 5 out of 5 by from Great helmet Fabulous for price lightweight and pretty ! Must have
    Date published: 2014-07-07
    Rated 5 out of 5 by from If you like Samshield, give this a shot I like this helmet - alot- especially at this price point. It is less bobble-headed looking than my CO AYR8, but not as trim as my IRH. It unfortunately is too round for my long ovalish head. Also, I have an important observation here. Both the Samshield (shadow mat) I tried and this One K are nearly IDENTICAL in appearance and size (except, I actually think the Samshield is weird looking without anything to break up the big round black matte ball-like appearance) and get this, they're both made in Korea according to their boxes. Coincidence? I think not. I bet they're made by the same manufacturer. The Samshield had a bit more padding but otherwise I did not see a difference between these two. If this fit me better I would have kept it. I am sad I can't get a good fit.
    Date published: 2014-06-03
    Rated 5 out of 5 by from Super comfy and cool! Love the easy care shell, the superior ventilation and the removable liner. This is a really nice helmet for the price.
    Date published: 2014-05-20
    Rated 5 out of 5 by from Nice Helmet! I bought this based on the recommendation of the Smartpak rep to replace my IRH Air, which kept slipping, even with added stuffing. She explained that the Air was rounder than the IRH Elite I use for schooling - so the same size wasn't comparable. She was right. This helmet fits so much better for a more oval head. Loved the look of the Air but this is nice looking also - with the added advantage of my being able to see where I'm going when landing after a jump! Good price, too.
    Date published: 2014-05-14
    Rated 5 out of 5 by from Very nice Helmet! I have been using IRH and GPA helmets; thought I would try this one since the one GPA cracked over the winter. I absolutely love it!
    Date published: 2014-04-21
    Rated 5 out of 5 by from the best helmet I've ever owned! I just got this helmet yesterday, since my horse knocked my other one off my head and it landed on the barn floor and the whole visor cracked :( I never liked the velvet OneK's, but when I saw that they came out with the matte one, I was so excited! It's so comfy and it fits perfectly, not to mention how nice it looks! I couldn't be happier :)
    Date published: 2014-03-14
    Rated 4 out of 5 by from Great for schooling! I bought this helmet for schooling and local shows and I love it! It is very low profile, and fits my head great. Would definitely recommend.
    Date published: 2014-03-03
    • 2015-05-24T09:03CST
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