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One K Defender Matte Helmet

One K - Item #21807
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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'!).

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You'll love our AutoShip because it's:
  • Focused on healthy s, because consistency is key
  • Easy to snooze or cancel online, anytime
  • Totally flexible - edit your order as often as you'd like
  • Your VIP pass to FREE SmartPerks benefits
PLUS! You'll save % on every shipment if you order this product on AutoShip
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Begin with the zone for the state you are in. Dates shown on the map indicate suggested start and end dates for Fly Stoppers™ shipments. You may want to shift a zone if your elevation or microclimate is unusual, or if you fall on the border between two zones. You can start anytime during the fly season. Choose "Year Round" for climates that have flies all year, and start now.
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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.
  • 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
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Hassle-Free Returns

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We put our products to the test in our barns and on our horses, so we're confident that you'll be thrilled with your purchase. However, we know that life in the barn can sometimes be unpredictable. That's why we've created a stress-free return policy. If you purchase an item and it doesn't meet your expectations, we want to know about it, take care of you and give you your money back.

Free Return Shipping on all Sized Items

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'!).

The Fine Print

We love our products and we're happy to take them back - even custom items. We'll happily take back everything from engraved halters to personalized jackets - even embroidered blankets that have been worn (minus the manure, please). But there are a few things we have to restrict returns on (silly federal regulations).

Undergarments
Health regulations require that undergarments (including bras) need to be in new condition (tags and packages intact) in order to be returned. (Even if it wasn't required, do you really want to shop from a store that takes back used undergarments?!)

Saddles
As riders, we know what a big investment a saddle is. That's why we're proud to offer the best Test Ride program in the business. You can keep our Test Ride saddles risk-free for five days, to really make sure you like the fit and the feel. We know that to truly try a saddle, you have to really ride in it. So go ahead and girth it up. Forget about wrapping your stirrup leathers. Try it with or without a saddle pad. Basically, treat it like you already bought it, so you can make sure you really want to. Because when you buy a saddle from us, we want to make sure you love it. Of course, we want our other customers to love their new saddles, too.
That's why we have a Test Ride option for each saddle we carry - so that all of the other saddles can stay in pristine condition, waiting for their new owners. For this reason, if you purchase a saddle outside the Test Ride program, it's still eligible for return, but must be free from any marks or damage.

So that's it. Seriously. Those are all of our "rules." Well, except the most important one - treating our customers the way we want to be treated. So if you have any questions or if there is anything we can do, please call us at 1-800-461-8898 or email CustomerCare@SmartPak.com. We are always happy to help.

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The reviews provided on this website represent the experience of the individual posting the review. We do not adopt, edit, or endorse any of the submissions posted within the reviews section. Rather, the reviews are part of an online community of animal owners that desire to share their particular experience with other individuals. These reviews are not a substitute for discussing the health of your animal with a veterinarian.

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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    Reviews

    One K Defender Matte Helmet is rated 4.7 out of 5 by 162.
    Rated 5 out of 5 by from Love the helmet For the last several years I bought this helmet (one just for shows, one in Blue and one for every day riding). They have always started off tight (I have a bony growth like a small horn) but use to it. So when the oval one was offered I figured it would not be as tight. Well it ended up being really loose to the point I couldn’t bend over it would slip right off. I still love this helmet but the oval one just didn’t fit like I wanted It to. Though I might try downsizing next time....hmmm
    Date published: 2018-09-27
    Rated 4 out of 5 by from Love it Very comfortable, very nice little looking helmet. I like the fact that the inside liner is removable for washing. This helmet seems like more for my money. The vents keep my head cooler, too. My only complaint is the chin strap sits at a funny angle.
    Date published: 2018-09-16
    Rated 5 out of 5 by from LOVE! I am a long oval FAN! CO helmets gave me a headache. GONE with this shape! The brown is stunning!
    Date published: 2018-09-13
    Rated 5 out of 5 by from Love it I love this helmet, it fits and looks great. I bought the regular round.
    Date published: 2018-09-10
    Rated 5 out of 5 by from Stylish comfortable helmet Been searching for a helmet that fits my oval head and well this not only fits well , but it’s really comfortable and stylish !!
    Date published: 2018-09-10
    Rated 5 out of 5 by from Love this helmet I have a small odd shaped head apparently and this is one of two helmets that just don't look absolutely ridiculous on me.
    Date published: 2018-09-10
    Rated 5 out of 5 by from Great and affordable Helmet I just bought my second One K Defender because I loved it so much. One of the more affordable options in helmets these days but still a great looking one. I love that you can remove and wash the liner as well as buy replacements for the liner if needed or if an extra is wanted.
    Date published: 2018-09-10
    Rated 5 out of 5 by from My favorite helmet I sustained a really bad fall in this helmet in May and the helmet protected me better than I have seen many helmets (including my GPAs). I immediately bought a new one of this same helmet to replace my old one and won't consider any other brand. Bonus that it doesn't make me look like an egg head!
    Date published: 2018-09-10
    Rated 5 out of 5 by from Perfect helmet for me I absolutely love this helmet. It’s beautiful, lightweight, and fits the shape of my head perfectly- like it’s not even there. I’ve had it four months, I ride at least about 3x a week and I can’t find anything bad to say about it so far. I love the removable liner so I can wash the interior and don’t breakout on my forehead. The removable liner is a must for anyone whos head sweats when they ride! I also love the chin strap because it has padded leather on it- looks nice and you don’t even know it’s there. Ive used Charles Owen JR8, Tipperary, international and ovation helmets before- they do not compare.. You get the best bang for your buck too, in my opinion. I don’t think I’ll go with any other helmet. I went with a small and it fits true to measurements for me. I would say my head is more oval than round shape. I it in the bag and don’t bang it around on things/treat it gently when not wearing it and it looks brand new!
    Date published: 2018-09-08
    Rated 5 out of 5 by from Beautiful helmet - cool and great-fitting! I bought the long oval in blue and it's beautiful and so comfortable -- cool in the Texas heat and great-fitting! I'm not have any trouble or discomfort with the chin strap, but this is the most expensive helmet I've ever owned:)
    Date published: 2018-07-19
    Rated 5 out of 5 by from Amazing I bought this a few months ago and recently was flipped over my horses head and landed straight on the top of my head. Thanks to this helmet I do not have a concussion and the plastic shell did not crack.
    Date published: 2018-07-03
    Rated 5 out of 5 by from This replaces a One K that I used for 4 years. Took a pretty hard fall and it did the job we all hope for. My old One K was the suede which I think looked a bit sleeker than the matte but my brain and skull don't really care what it looks like. Thanks Smartpak for including a small and medium liner for the medium helmet. I have very short hair and definitely needed the snugger fit.
    Date published: 2018-06-11
    Rated 5 out of 5 by from I bought this for my 10 year old daughter after a fall and break of her old helmet. I was looking for something safer and that covered the back of her lower head better. They sent two helmet pads with the helmet and a note saying the second pad was a gift if it created the perfect fit. That additional pad made the fit perfect and now she can grow into the helmet so it makes the price just right for me.
    Date published: 2018-06-05
    Rated 5 out of 5 by from Helmet Love the way it fits my head! Keeps my head cool when I ride.
    Date published: 2018-05-14
    Rated 5 out of 5 by from Perfect fit! I can't say enough good things about this helmet. My favorite thing is that it fits perfectly and is so comfortable I don't even feel it!
    Date published: 2018-04-19
    Rated 5 out of 5 by from Great fit! I have a hard time finding helmets that fit me properly. After searching for a new show helmet, I was happy to learn One K offered a round fit helmet. It's perfect!
    Date published: 2018-04-09
    Rated 5 out of 5 by from Great value, great helmet The removable liner and the generous vents make this a great helmet. The price is right, too!
    Date published: 2018-03-31
    Rated 5 out of 5 by from Great looks and nice quality. My daughter picked this helmet out for her birthday. It looks so nice on her. It will be used only for schooling. It is our first One K purchase, so we hope it holds up well.
    Date published: 2018-03-01
    Rated 5 out of 5 by from Awesome helmet Bought this helmet just a few days ago and I'm already in love. I've been riding in a Charles Owen for a couple years now and over time it had stretched out quite a bit to the point where I no longer felt safe wearing it. Decided to purchase a OneK as my next helmet investment and I won't be going back! Much more lightweight and breathable and I don't feel like as much of a mushroom head! I went with a medium round fit and it's perfect!
    Date published: 2018-02-20
    Rated 5 out of 5 by from great fit! i bought this last week and am very pleased with the purchase, it fits perfect. its so very comfortable and has a very chic design.
    Date published: 2017-12-30
    Rated 5 out of 5 by from Fits my head perfectly! As I have never ordered a hat from Smartpak, I was unsure of the sizes! But it fits perfectly and I really like the style too!
    Date published: 2017-12-29
    Rated 5 out of 5 by from So comfortable! I just got this helmet a few weeks ago and love how comfortable! Can’t say how durable it is but I’ve definitely have high hopes for it! :)
    Date published: 2017-12-15
    Rated 3 out of 5 by from Nice helmet but strange fit I love the look of the helmet. But the harness sits very far forward; almost on my chin. The edges of the straps also feel very sharp. However the main issue for me was I felt it didn't cover enough of my head and didn't have the same weight/density/coverage that my Charles Owen does. It's very nice looking but I just don't know how well it would hold up with a fall.
    Date published: 2017-11-19
    Rated 5 out of 5 by from comfortable! I'm really enjoying my new helmet - it's the first helmet I've ever owned that felt just right on my head. Very secure, and comfortable.
    Date published: 2017-11-15
    Rated 5 out of 5 by from Fits perfectly Very comfortable fit. Love the blue color. Added bonus of the removable and washable liner. Very satisfied.
    Date published: 2017-10-30
    Rated 4 out of 5 by from Love it I love this helmet. It is super lightweight and perfect for Florida riding. The fit is also great. My only complaint is that the chin strap leaves black marks under my chin after I ride. I'm not sure if this is typical if these helmets or not. I have another One K Helmet with suede that does not leave marks. Overall great helmet.
    Date published: 2017-10-17
    Rated 5 out of 5 by from Gorgeous color, great fit. This is my second OneK. I love these helmets. Comfortable, nice profile, reasonable price.
    Date published: 2017-10-14
    Rated 4 out of 5 by from Beautiful helmet I bought this helmet to have a new schooling helmet, but it is so nice, I'm saving it for showing
    Date published: 2017-10-14
    Rated 5 out of 5 by from So comfy and great looking! I had a GPA for 12 years and knew I was really due for a new helmet. I got the OneK and I love it! I have the matte black and dirt wipes right off. The only thing I have to get used to us the chin strap sit a little far forward on my chin compared to the GPA strap.
    Date published: 2017-10-12
    Rated 5 out of 5 by from Very comfortable and good looking Bought this to replace my Charles Owen which i wasn't a huge fan of. I got the oval long and it is SO COMFORTABLE!! Great and beautiful helmet for a fraction of the cost!!! My head measured 56 cm, so i got the med and large; the medium ended up being a bit big, so we may have measured wrong. I just added a bit of extra stick in foam padding and it is good to go though.
    Date published: 2017-10-10
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