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One K Defender Series Riding Helmet

This Item Ships For Free!
Shop All One K Helmets

One K Defender Series Riding Helmet

$179.88 - $289.95
One K Defender Matte Black XS Reg
In Stock: 1
Price: $289.95
  • Color: Black
  • Helmet Size: XS
  • Helmet Shape: Reg
One K Defender Matte Black XS Long Oval
In Stock: 2
Price: $289.95
  • Color: Black
  • Helmet Size: XS
  • Helmet Shape: Long Oval
One K Defender Matte Black SM Reg
In Stock: 4
Price: $289.95
  • Color: Black
  • Helmet Size: SM
  • Helmet Shape: Reg
One K Defender Matte Black SM Long Oval
In Stock: 2
Price: $289.95
  • Color: Black
  • Helmet Size: SM
  • Helmet Shape: Long Oval
One K Defender Matte Navy SM Reg
In Stock: 2
Price: $179.88
  • Color: Navy
  • Helmet Size: SM
  • Helmet Shape: Reg
One K Defender Matte Black MD Reg
In Stock: 3
Price: $289.95
  • Color: Black
  • Helmet Size: MD
  • Helmet Shape: Reg
One K Defender Matte Black MD Long Oval
In Stock: 2
Price: $289.95
  • Color: Black
  • Helmet Size: MD
  • Helmet Shape: Long Oval
One K Defender Matte Black LG Reg
In Stock: 3
Price: $289.95
  • Color: Black
  • Helmet Size: LG
  • Helmet Shape: Reg
One K Defender Matte Black LG Long Oval
In Stock: 3
Price: $289.95
  • Color: Black
  • Helmet Size: LG
  • Helmet Shape: Long Oval
One K Defender Matte Black XL Reg
In Stock: 4
Price: $289.95
  • Color: Black
  • Helmet Size: XL
  • Helmet Shape: Reg
One K Defender Matte Black XL Long Oval
In Stock: 1
Price: $289.95
  • Color: Black
  • Helmet Size: XL
  • Helmet Shape: Long Oval
One K Defender Matte Navy XL Reg
In Stock: 1
Price: $179.88
  • Color: Navy
  • Helmet Size: XL
  • Helmet Shape: Reg

Riding Warehouse wants you to be completely satisfied with your purchase. Items can be returned at any point in new condition within 365 days of the original invoice date.

Products returned in new, store-bought condition are eligible for exchange, refund, or Riding Warehouse store credit for the full value of your purchase.

Products returned that are unable to be returned to stock are eligible to receive Riding Warehouse store credit for the full value of your purchase. Please note that while we want you to be happy with your purchases, an excessive number of used returns within a twelve-month period may limit your eligibility for store credit.

Products returned beyond 365 days from the original invoice date may be eligible for partial store credit at the sole discretion of Riding Warehouse.

Original shipping charges are non-refundable.

Overview

Enter the show ring with sophisticated style and undeniable comfort with the One K Defender Riding Helmet. A sleek injection-molded outer shell with discreet stainless steel ventilation panels boasts a professional finish to appeal to even the most discerning of fashion-forward equestrians. Modern technology ensures maximum safety while unique user-friendly features provide optimal comfort, durability, and ease of use.

With a washable, quick-dry, anti-microbial lining system, the One K Defender stands true to its name to fight moisture build-up and prevent odor and discomfort. A unique padded harness with a soft synthetic suede lining features Velcro adjustment options for a truly customized fit while the Fastex® chin buckle allows one-handed ease of use!

Key Features

  • Polycarbonate/Advanced ABS Composite Outer Shell
  • Washable, Quick-Dry Lining with Anti-Microbial Protection
  • Sleek, Stainless Steel Mesh Ventilation Channels
  • Comfort Padded Harness with Soft Synthetic Suede Lining
  • Customizable Velcro-Adjustment Chin Strap with Fastex® Buckle
  • Painted Matte Finish for a Sleek & Professional Appeal
  • ASTM F1163-15/SEI Certified 

Product Details

One K offers a 3-year replacement policy if your helmet is in an accident. See information about this policy here.

Sizing

Please Note: Check the sizing chart and measure, as these helmets may run small.

Size Head Circumference Cap Size
XS 51 - 52 cm 6 3/8 - 6 1/2
SM 53 - 54 cm 6 5/8 - 6 3/4
MD 55 - 56 cm 6 7/8 - 7
LG 57 - 58 cm 7 1/8 - 7 1/4
XL 59 - 60 cm 7 3/8 - 7 1/2
XXL 61 - 62cm 7 5/8 - 7 3/4

See how a helmet should correctly fit with Kim Gentry in this helpful sizing video

Videos

Customer Reviews

Previous Feedback  

Comments: THE BEST HELMET EVER! I love the fit on these helmets - it's perfect. They are comfortable and fit snugly. Will be my go to for now on and you can't beat Riding Warehouse's shipping! 
From: Alexandra - San Jose, California, USA 

Comments: I've had many helmets over the years, and the One K has by far been my favorite. The sleek shell of the defender not only looks good, but is comfortable, and the removable inserts make it a breeze to wash or to change the fit of the helmet for when I have my hair in a ponytail. The cherry on top is that it is budget friendly!  
From: Cenn - St. Charles, Illinois, USA 

Comments: Beautiful, elegant style and wonderful fit. I have a very uneven shaped head and subsequently tried on numerous helmets to no avail. Fortunately this helmet fits like a glove. I love the comfort of the foam in the liner and the ability to remove, machine wash, and replace the liner. I also love that I can simply move up to a larger size liner when I put my hair in a net/grow my hair out. RW customer service was excellent and shipping across the country was so fast. *Almost* want to buy another one in the rose gold! 
From: Janice- Texas, USA 

Comments: I put this helmet on, and I swear I heard angels singing. I was a bit worried about S/M/L sizing, as I typically wear either a 6 3/4 or a 6 7/8, but I ordered a medium long oval and hoped for the best. It is PERFECTION. I can turn my head upside down without fastening the harness and the helmet does not fall off, yet I just walked around my house for 2 hours and there's no hint of a pressure spot on my forehead or a headache, which is my usual problem trying to make round-ish helmets fit my oval head. I don't love the angle of the chin harness - it seems to come too far forward, almost jabbing into my chin, but it seems like that will stretch and soften with time. Thanks to RW's generous return policy, I tried and returned 2 sizes of the IRH Elite (6 7/8 was too big, but 6 3/4 seemed perched) and the CO Pro II. Glad the 4th (eek) time was finally the charm. Thank you for carrying the long oval shape, and for not cutting me off as a customer after so many returns ;)  
From: Jennifer - Pittsburg, Pennsylvania, USA 

Comments: This helmet gets a lot of compliments. I just took a fall wearing this helmet and while I'm pretty well bruised and the helmet needs to be replaced I can say the my head was well protected.  
From: Yvonne - Rochester, New York, USA 

Comments: Fits great and feels very secure. I keep a spare liner to switch out every few rides. It stays comfortable for long rides and never makes my head hurt. I don't notice a huge difference with keeping my head cooler, though.
From: Abigail - Petaluma, California, USA

Comments: Ah-mazing helmet! Worth every penny. Fits snugly enough - it feels secure but doesn't smother you. Looks really good too!
From: Rebekah - Turlock, California, USA

Comments: Super profile with a beautiful color. The first helmet I ordered had issues with the liner, but Riding Warehouse promptly exchanged it for me. Couldn't be happier with this purchase! 
From: Dani- Milwaukee, Wisconsin, USA 

Comments: Best fitting helmet and at a reasonable price! Great lightweight helmet that actually fits my tiny head. Vented and comfortable even with our hot, humid summers. The lining can be taken out and washed. Love this helmet. 
From: Shelton- Charleston, South Carolina, USA

Comments: It took me a long time to find a helmet that I liked the look of, and I am so glad I found the One K... I LOVE it...it is super easy to keep clean too!!
From: Stephani - Anchorage, AK, U.S.A.

Comments: Love the profile and is the first helmet that actually fits my small head! Service was excellent and arrived as scheduled per tracking! Will definitely shop here again! Thx!
From: Carole - Peach Bottom, PA, U.S.A.

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