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One K (#21807)

One K Defender Matte Helmet

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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 request a return with a FREE SmartPak return label from your Order History within 60 days of 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'!).

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Overview

Why We Love This

One K™ Defender riding helmets boast the perfect synergy between advanced technology and aesthetically pleasing design. This helmet features a polycarbonate and advanced ABS composite outer shell that’s tough but lightweight with a modern matte finish. It’s offered in both an oval shape and a round shape so that you can find the perfect fit for your head. You’ll love that the liner is moisture wicking, quick drying, anti-microbial, and washable to keep you cool, dry, and comfortable. Plus, the harness is padded for comfort and lined with easy-to-care-for synthetic suede to keep you as comfortable as you are stylish. It even has a Fastex buckle that makes taking it quick and easy to take on and off. Additionally, you’ll have plenty of ventilation with two side, two front, one back, and two center stripe vents for a total of seven vents. Last but not least, this helmet is ASTM/SEI F1163-15 certified, so you can have peace of mind that your head is in good heads. With enough features to appeal to those seeking everything a horseback riding helmet could offer, wrapped in a stylish package that traditionalists can appreciate, One K™ has the best of both worlds.

Additional One K Helmet Liners also available!

Imported

CAUTION: Safety equipment must fit properly and be appropriately secured with manufacture approved parts only. Altering or adding to safety equipment voids warranty and can result in injury. As a safety precaution, inspect all products prior to each use.

For additional information on fit, watch our video on how to fit your helmet. Click Here!

  • Polycarbonate and advanced ABS composite outer shell is tough but lightweight
  • Offered in oval and round shapes for a great fit
  • Inner lining is anti-microbial, moisture wicking, quick drying, and washable
  • Comfort padded harness with synthetic suede lining and Fastex buckle is comfortable, easy to use, and stylish
  • ASTM/SEI F1163-15 certified
  • Lots of vents to keep you cool and dry
  • Stylish design looks great in the ring
Key Specifications
  • ASTM/SEI: Yes
  • Oval: Yes
  • Round : Yes
  • STILL HAVE QUESTIONS? SEE Q&A
  • 100% Happiness Guarantee
    100% Happiness Guarantee
    At SmartPak, your happiness is at the core of everything we do. We put our products to the test in our barns and on our horses, and back every order with our world-class customer service so that you can shop with confidence. As part of our Happiness Guarantee, we promise you:
    • Expert advice from riders
    • Free shipping every day
    • Free return shipping on sized items
    • Hassle-free returns up to 365 days after purchase
Ingredients
(Maintenance Dose = )
Ingredient Amount
Sizing
What Customers Say:
Sizing Chart for One K Defender Matte Helmet
Specifications
ASTM/SEI Yes
Oval Yes
Round Yes
Reviews
One K Defender Matte Helmet is rated 4.7 out of 5 by 187.
Rated 5 out of 5 by from Comfortable helmet that fits great Love the removable inner liner! Highly recommended. Excellent helmet at a great price!
Date published: 2021-10-22
Rated 5 out of 5 by from So comfortable This is the best fitting helmet I’ve ever owned, plus it is very comfortable in hot weather
Date published: 2021-08-12
Rated 4 out of 5 by from AMAZING HELMET!! Disappointing chin strap. This helmet is amaaaazing. It feels as supportive as high waisted, stretchy jeans on a bloated day…but for your head lol. The liner has a memory foam feeling which is nice because my M-round is still getting molded to my head shape (perfect fit, not too tight) so I don’t have to worry about headaches. BUT THE CHIN STRAP. If you lengthen it too much, you’re not able to Velcro it (see pic). I guess I will just rock the double chin? Anyways, this helmet is pure gold. Get it! But just ignore the chin strap entirely.
Date published: 2021-07-09
Rated 5 out of 5 by from My favorite helmet! The most comfortable helmet I've owned. I love it so much I got it in all colors. It fits my head perfectly, and especially love the fact that I can choose between long oval and round fit! The long oval has been the best thing yet for my head shape. No more front head pressure points! The matte material is so easy to clean with a damp cloth, and I can take the padding out and wash it too. This helmet is perfect for every use no matter if you want to use it for schooling, clinics, or shows. I personally always have two of the same to keep one nice for the show.
Date published: 2021-04-19
Rated 5 out of 5 by from Sleek style and great quality! I had to get a new helmet after falling in my old one and hitting my head pretty hard. I know a bunch of my riding friends have this brand of helmet so I decided to try it out and I love it more than my old one! It fits really well and looks so nice when I’m wearing it!
Date published: 2021-03-03
Rated 5 out of 5 by from Perfect fit I was due to purchase a new helmet and decided to get this one. I wore it last night during my hack and it fit perfectly and was comfortable throughout my whole ride. I also love how easy and convenient the adjustment for the chin strap is, and how easy to clean the helmet is.
Date published: 2021-03-03
Rated 5 out of 5 by from Best Helmet Brand for a Great Price Purchased about a month ago - after attending a show and seeI got a teammate get thrown, it was decided I needed a better, safer helmet. I chose the matte navy- it is both beautiful and comfortable! The price was much lower than on other sites and I’m very happy with it!
Date published: 2021-01-20
Rated 5 out of 5 by from Love the oval option, nice helmet! I had quite a bit of trial and error with other brands before I found the right helmet to fit me. I figured out that it was mostly because of the oval shape of my head, so decided to try the One K since they do have the oval option. I measure just a touch over 57cm, so at first tried the size Large Oval. This helmet was much too big for me, even with the strap snugged all the way up. I exchanged for the Medium Oval and it fits like a glove! Very nice helmet and I love SmartPaks exchange policy!
Date published: 2020-11-05
Rated 5 out of 5 by from Great fit! Very comfortable and perfect for schooling and showing.
Date published: 2020-10-05
Rated 5 out of 5 by from Perfect fit!! I love that they offer a helmet in long oval, the only helmet that fits and does not give me a headache!!
Date published: 2020-10-02
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Q & A
Videos
One K Defender Matte Helmet Review
Katie from SmartPak talks about why she thinks the One K Defender Matte Helmet (http://bit.ly/1F0MsaV) is so smart. The smartest reason to get yours at SmartPak? Free Shipping Both Ways! At SmartPak.com, you’ll get free shipping every day on all orders over $75 and free returns on all sized items. Just another way it pays to be $mart.
How to Shop for a Helmet
Have you ever struggled with the idea of buying a helmet online? Watch this video for tips & tricks on getting the right helmet fit.

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