Product Code 468259

One K™ Defender Helmet

MSRP $289.95

(3 customer reviews)
One K™ Defender Helmets boast the perfect synergy between advanced technology and aesthetically pleasing design with an easy to clean finish.

Additional information

Sizes X-Large, X-Large Long Oval, X-Small, X-Small Long Oval, XX-Large, XX-Large Long Oval, Small, Small Long Oval, Medium, Medium Long Oval, Large, Large Long Oval
Colors Black Matte, Brown Matte, Navy Matte
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The Defender Riding Helmet features glossy or matte Polycarbonate and Advanced ABS Composite outer shell; injection molded shell design; washable quick-dry, moisture wicking, anti-microbial liner; stainless steel mesh; comfort padded harness with synthetic suede lining, hook & loop adjustment, and Fastex buckle; two side, two front, one back, and two center stripe vents. One K™ Helmets boast the perfect synergy between advanced technology and aesthetically pleasing design. With enough features to appeal to those seeking everything a helmet could possibly offer, wrapped in a package that traditionalists can appreciate, One K™ has the best of both worlds. Certified to ASTM standards.

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  • Glossy or Matte Polycarbonate and Advanced ABS Composite outer shell Two side, two front, one back, and two center stripe vents
  • Comfort padded harness with synthetic suede lining, hook & loop adjustment, and Fastex buckle
  • Washable quick-dry, moisture wicking, anti-microbial liner
  • ASTM/SEI F1163-15 certified

Helmet Shape

icone-helmetshape-roundCreated with Sketch.


Is shaped for a head which has almost identical front-to-back and side-to-side measurements.

icones-helmetshape-ovalCreated with Sketch.

Long Oval

Is shaped for a head which is longer front-to-back (from forehead to the back of the skull) than it is side-to-side (ear to ear).

One K™ Defender Helmet Features

468259 Defender Helmet
Helmet Ventilation


Ventilation mesh on both sides, front, top, and back of helmet for a sporty look and maximum airflow.

Shorter harness


Polycarbonate and Advanced ABS Composite Shell.

Stainless Steel

Stainless Steel

Stainless Steel Mesh won’t rust.

Stainless Steel

Fastex Buckle

3 reviews for Defender Helmet

  1. Vermont Rider

    This is an excellent riding helmet. I bought mine at a local tack shop, and it was good that I did, because I was able to try on different helmet/helmet liner combinations. I have a large head (size 7 3/8) and many helmets look ridiculously big on me. The One K Defender in large, combined with a medium liner, resulted in a perfect fit. The color I chose was matte brown, which is very pleasing. The helmet itself has more-than-adequate ventilation. I trust that it will protect me in the event of a fall or running into a tree limb (I trail ride, averaging 160 rides per year). I feel that having the chance to swap and switch liners to get a perfect fit justified paying full retail for my One K rather than ordering one from an online discount vendor. Also, I like to support local businesses, without which one would never have a chance to try things on in person. I am very happy with this helmet and recommend it unreservedly.

  2. Judy

    Since I work for a major equine retailer, I have the privilege to try a number of helmets, as most people do anyway, but I also get the training in helmet fitting as well. When I tried the One K, I was delighted in its features and benefits. It is lightweight and vented which was a huge plus for me especially during the summer months on those hot training days. It has cutting edge features and I love the look. This helmet fits me perfectly and I love that it comes in colors. I am now contemplating buying a second one, just not sure I want the navy or grey! Thanks for making such a super helmet that is truly affordable for the amateur rider!!!

  3. Sarah

    I recently bought one of these helmets as my old helmet no longer would fit me correctly… I had a bear fatal, Traumatic Brain Injury in December of 2009. Part of the agreement for me to go back to riding horses was wearing a helmet because I was told I would not survive another hit to the head. I recently had another brain surgery related to this original injury and am having some unforeseen side effects that effect my vision and balance extremely. So I was encouraged to get another helmet. After extensive research, I saw this to be the best option for me… I can say this is the most comfortable lightweight yet secure helmet that I have ever worn!! Absolute comfort with my thick hair, doesn’t make my head sweaty and itchy like my old helmet and it’s so light weight I don’t feel it on my head yet it’s so secure and well built, I feel confident If anything was to happen. Definitely recommend this brand and will be buying some for my nieces as they grow up!

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**ASTM F1163-04A AND CE EN 1384 CERTIFIED HELMETS (HELMET NOTICE, DISCLAIMER, AND WARNING)Dual Certified All equestrian sports are inherently dangerous and involve the risk of serious injury or death. Riders using these products ride at their own risk with full knowledge of the hazards and risks associated with their activities. Helmets are designed for equestrian use only. Helmets cannot offer complete protection from injury or death to riders in case of fall, collision, impact, loss of control or otherwise. Helmets cannot protect areas of the head that are not covered. Helmets offer no protection against injuries involving forces other than impact. CAUTION: HELMETS MUST FIT WELL AND ALL RETENTION STRAPS MUST BE SECURELY FASTENED. Helmets are constructed so that the energy of an impact may be absorbed through partial destruction of the helmet. Helmets that suffer an impact should be destroyed and replaced. The protective qualities of helmets may be compromised by prior impact, age, use and many common substances. Always follow the manufacturer’s recommendations before applying cleaning agents, paints, or adhesives. English Riding Supply disclaims any responsibility for injuries or death incurred while wearing any of the helmets offered for sale. Representations regarding testing results, equipment ratings, product specifi cations, ASTM and/orSEI standards, and the adequacy of all such standards and designations are made solely by the product’s manufacturer. English Riding Supply does not warrant or confirm the representations of the manufacturers. English Riding Supplly makes no representations express or implied regarding the fi tness of these products for any particular purpose nor the extent to which the products protect riders from injury or death.

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