SKU: 19486498227

O'Neal - Sierra II Flat Helmet

Sale price$145.79 Regular price$161.99
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Shipping Estimate
USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Jul 15 - Jul 20

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For Your Every Summer RSVP, with Code: SUMMER15

Description

O'Neal - Sierra II Flat HelmetO'Neal Sierra II Flat Helmet The O'Neal Sierra II Flat Helmet feels like that dependable lid you grab every weekend, light, well vented, and ready for whatever track or trail you throw at it. Balanced shell weight, efficient venting, and a plush liner that keeps its shape moto after moto. Why We Like It: Everything about it feels dialed: airflow, comfort, and control without unnecessary extras. Why Itll Work for You: If you want straightforward

O'Neal - Sierra II Flat Helmet

The O'Neal Sierra II Flat Helmet feels like that dependable lid you grab every weekend, light, well-vented, and ready for whatever track or trail you throw at it.

Balanced shell weight, efficient venting, and a plush liner that keeps its shape moto after moto.

Why We Like It:
Everything about it feels dialed: airflow, comfort, and control without unnecessary extras.

Why It’ll Work for You:
If you want straightforward performance, easy goggle fit, and comfort that holds up, this helmet just works.

Variants / Options:
Available in several colorways and sizes for a dialed-in fit.

Key Features:

  • Lightweight, balanced shell design

  • Airflow channels for active cooling

  • Moisture-wicking comfort liner

  • Wide goggle port and adjustable peak

  • Shell in constructed with ABS

  • Weight: 1590g (± 50g)

  • Moisture wicking, removable/washable air channeled comfort liner

  • Vent holes for optimal ventilation

  • Integrated face shield

  • Height adjustable helmet shield

  • Padded Chin Strap with Double-D safety lock

  • Meets DOT and ECE 22.05 safety standards

  • Designed for Street, Enduro, Side by Side and Adventure Bike’s

  • Replacement parts available


Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 19486498227

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4.4 ★★★★★
Based on 21 reviews
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J
Verified Purchase
Jessica Beasley
Massapequa, US
★★★★★ 4
Prom
Suit was a little too big, so had to have it taken in, other than that, it is perfect
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 20, 2025
E
Verified Purchase
Eugene
West Palm Beach, US
★★★★★ 2
Small and Stiff, that’s what she said!
Refunded… this thing is cut small, has a short crotch area, like women’s pants and the material although nice is stiff with no give at all… gotta be a skinny dude to wear this one. I suggest a size or 2 up
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 15, 2026
J
Verified Purchase
jancie brown
Draper, US
★★★★★ 5
Well made
Very well made. Fit 5'5 130lb preteen perfectly for a sneaker ball. The material is thick so keep that in mind if purchasing during a hot month.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 26, 2024
J
Verified Purchase
Jaylene
Dallas, US
★★★★★ 5
Perfecto
Muy bonito 😊
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on June 4, 2024
H
Verified Purchase
Heilee matlock
Lowell, US
★★★★★ 1
Do not biy
Unfortunately this material is a great example of getting what you pay for. The fit is off and the material makes it so tacky.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 6, 2025

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