Skip to content
PLEASE NOTE: You may experience errors on our site when using Internet Explorer 10 or lower. Please consider updating your browser, or download Google Chrome.
Ship speed applies to in stock items, pending location. Does not include personalized items like engraving, embroidery, SmartPaks, or PortionPaks. Complete details on our Shipping Policies page.
All of our supplement and product expertise is just a text away. Ask questions, manage your account, and place orders by texting 26756 from your mobile phone. Have a great ride!

Our experts are available
Monday – Thursday 9:00 am – 5:00 pm EST
Friday 9:00 am – 3:00 pm EST

*By texting 26756, you're giving SmartPak your consent to text you to help resolve your issue, including automated replies, at the number you provided. To opt out, text STOP to 26756. Text HELP to 26756 for info. Msg&rates may apply. Consent to receive texts not required to buy products. Terms & conditions and the full Text Message Privacy Policy can be found at https://www.smartpakequine.com/content/2waytextTC in case you're interested.
SmartPerks Putting your horse's supplements on AutoShip helps you take great care of your horse, so we take great care of you with SmartPerks! When you order your horse's supplements on AutoShip, you're automatically* eligible for our FREE SmartPerks benefits, including:
Learn more about SmartPerks
*At least one individual AutoShip supplement or horse's SmartPaks must be over $40. Some exclusions apply.
Visit SmartPak.com/SmartPerks or call 1-800-461-8898 for details.

Qualifying Items

Qualifying items are eligible for free shipping, every day. Look for the badge below on the product page to confirm that your item ships free!
SmartPerks
Free Shipping

Ride Along Items

Ride Along items are eligible for free shipping when shipped with your next AutoShip order or any qualifying item. Look for the badge below to identify a Ride Along item.
Ride Along Item
Ships free with a qualifying item
Clicking on the following image links will update the image above.
Clicking on the following image links will update the image above.
colors available

One K Defender Jr Helmet

One K - Item #29873
Our Price: List Price:
Our Price: Our Price: Sale Price: : $ (%) :
Member Price:
(Members save 5% at SmartPak)
:
SmartPerks Price:
(Because you have supplements on AutoShip, you save an extra 10% on this and all other SmartPak tack & apparel items!)
Your Price:
(You save 5% as a member of . And, because you have supplements on AutoShip, you save an extra 10% on this and all other SmartPak tack & apparel items!)
SmartPerks Price:
(Because you have supplements on AutoShip, you can save an extra 10% on this and all other SmartPak tack & apparel items! Enter promo code PERKS at checkout.)
Your Price:
(You save 5% as a member of . Because you have supplements on AutoShip, you can save an extra 10% on this and all other SmartPak tack & apparel items! Enter promo code PERKS at checkout.)
SmartPerks
Free Shipping (Details)
(Details)
Ships free with a qualifying item
Free Return Shipping
Free Return Shipping

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'!).

Customize your program:
Selecting any options will update the details accordingly with respect to the product

FINAL SALE - This item cannot be returned or exchanged.

FINAL SALE - This item cannot be returned or exchanged.

- +
Just left - order today! Don't wait - just a few left!
on every AutoShip order (Details)

days
(Discounted price will be reflected in your cart)
You'll love our AutoShip because it's:
  • Focused on happy riders - never worry about running out!
  • Easy to snooze or cancel online, anytime
  • Totally flexible - edit your order as often as you'd like
PLUS! You'll save % on every shipment if you order this product on AutoShip
(Details)
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
Price for one-time shipment:
Find zone
How to choose
AutoShip price: Price per shipment:
AutoShip Savings applied
Start date: Customize your program for estimated start date. View estimated schedule
:
Zone Map
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.
Program Type
Regular Programs:
Premium Programs:
Shipment/Application Frequency
Ships every 4 weeks. For low to average fly levels, frequent manure management and few neighbors.
Ships every 3 weeks. For high fly levels or weekly manure management or nearby livestock.
Required: (Optional)
These are for:
Sign in to choose an existing
Order within and have it by
Shipping to
Est. arrival times vary,
with some as soon as
Shipping to
Order within and have it by
Shipping to
Add these items to your cart to get your estimated arrival date.
Shipping to
Please call 1-800-461-8898 to order this product.
We're bringing you this product at the lowest price allowed by the manufacturer so you won't find it cheaper anywhere else. This also means we can't apply any further discounts or promotions.
We're sorry, but certain colors/sizes are sold out and are no longer available.

Why We Love This

Finally, a One K™ designed for children riders in Junior sizing, offering the same protection, quality and comfort as the current One K™ range, but with smaller internal helmet diameter, a thicker padded liner, and a smaller chin strap which is 15mm shorter in length than the adult sizes. Certified to ASTM standards.

Additional One K Helmet Liners also available! 

Imported.

Helmets Comparison Chart

Check out the other items we offer from One K helmets Here!
  • 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
  • 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
  • SEI/ASTM F1163.15
(based on )
of customers would recommend this product to a friend!
Tell us what you think!

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.

  • Review 0
  • Votes 0
  • Discipline:
  • Expertise:
  • Product
    Experience:
  • Competitor:
Quality
Value
Palatability

Helpful?

Ingredients

(Maintenance Dose = )
Ingredient Per Serving Per Pound

Sizing

Child's helmet, please refer to size chart.

XS - 47-48CM (5 7/8 - 6)

S - 49-50CM (6 1/8 - 6 1/4)

M - 51-52CM (6 3/8 - 6 1/2)
What Customers Say:
sizing chart

You Might Like

    Customers Also Shopped For
    Low profile lightweight fiberglass shell with a highly ...
    Description:
    Low profile lightweight fiberglass shell with a highly ventilated airflow system. It has a synthetic leather finish with black gloss vent & black patent piping detail and crown comfort padding in breathable high tech microfiber. Four point padded synthetic leather ...
    Elegantly styled, the jR8 is an economical helmet ...
    Description:
    Elegantly styled, the jR8 is an economical helmet that exceeds required safety standards both in the US and Europe, keeping you safe in the saddle. Low-profile and covered in weather-resistant microfiber suede with a soft, adjustable nylon harness, the jR8 ...
    Just when you thought riding couldn’t get any ...
    Description:
    Just when you thought riding couldn’t get any “cooler.” The Charles Owen Pro II has ventilation holes in the front and rear for maximum airflow and ultimate comfort. The removable cover has a visor and mesh front that will keep ...
    Women will absolutely love Star Lady when they ...
    Description:
    Women will absolutely love Star Lady when they will wear it thanks to the incomparable technical features that guarantee comfort, safety and high performances. The molded outer shell, in ABS, is very resistant and light. It’s covered with a special ...
    The Mountain Horse Aero Pro Helmet first features ...
    Description:
    The Mountain Horse Aero Pro Helmet first features a trendy large vent look, chrome brim accent and contrast piping. Includes an easy adjust dial for a sung fit. certified to ASTM standards. Made in the USA. Helmets Comparison Chart
    The Defender Chrome Stripe Riding Helmet features matte ...
    Description:
    The Defender Chrome Stripe Riding Helmet features 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 ...
    The Defender Rose Gold Stripe Riding Helmet features ...
    Description:
    The Defender Rose Gold Stripe Riding Helmet features 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, ...

    Reviews

    One K Defender Jr Helmet is rated 5.0 out of 5 by 1.
    Rated 5 out of 5 by from Fantastic Jr. Helmet This is a great helmet for a junior rider. Lower profile and better fit for a small head which is imperative for safety. Looks great and durable. Glad there is finally a JR helmet available for children that is great quality and safe
    Date published: 2019-01-11
    • y_2020, m_11, d_29, h_16
    • bvseo_bulk, prod_bvrr, vn_bulk_3.0.12
    • cp_1, bvpage1
    • co_hasreviews, tv_0, tr_1
    • loc_en_US, sid_19873, prod, sort_[SortEntry(order=SUBMISSION_TIME, direction=DESCENDING)]
    • clientName_smartpak
    • bvseo_sdk, net_sdk, 3.2.0.0
    • CLOUD, getContent, 94ms
    • REVIEWS, PRODUCT

    Q & A