30 Day Unconditional Guarantee
For Trek, Bontrager and Electra products, if for some reason you're not 100% happy with your purchase, you can return it within 30 days for a refund - no questions asked!
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How to clean your bike helmet
To ensure that your bike helmet looks and performs its best, it's important to properly clean and care for it. Check out our simple guide to learn how to maintain your bike helmet. It's easy to do and takes little time!
Read moreProduct features
Rally WaveCel mountain bike helmet
An off-road helmet with WaveCel technology that balances comfort and performance for trail riders who value safety.
What is WaveCel?
WaveCel is a collapsible cellular structure that lines the inside of your helmet. It works like a crumple zone that absorbs the force of an impact before it reaches your head. Read the study to learn more. You’ll never want to ride anything else again.
Virginia Tech validation
All WaveCel helmets received the highest rating from Virginia Tech’s third-party testing facility. This unbiased assessment proved WaveCel helmets to be among the highest level of protection available to cyclists with a 5-STAR rating.
BOA® fit system
Easily secure and adjust the helmet fit with just one hand.
Drop-in coverage
The extended, back-of-helmet shell offers additional rear protection.
LockDown strap dividers
Easily adjust straps to fit perfectly with adjustable, lightweight strap dividers.
Soft helmet pads
Super-comfortable internal pads wick moisture on hot days and hard efforts and are easy to wash after a full day of fun.
A TIME Magazine Invention of the Year
Trek's breakthrough technology was named TIME Magazine's list of 100 Best Inventions making the world better, smarter and even a bit more fun. From TIME ©2020 TIME USA LLC. All rights reserved. Used under licence
Crash Replacement Guarantee
With our Crash Replacement Guarantee, we will provide you with a free replacement helmet if it is involved in a crash within the first year of ownership. Simply contact us or your local retailer with the crashed helmet, original sales receipt, details of the incident and a return address for your replacement.
Learn more30-Day Unconditional Guarantee
If for any reason you’re not satisfied with a Bontrager or Trek aftermarket purchase, return the item, along with the original sales receipt to the original place of purchase within 30 days for an exchange or refund. Think of it as a 30-day test ride.
Learn moreHelmet Fit and Sizing
For your helmet to do its job, it's important that it's sized properly and fits well. Reference our sizing guide at the link below to find your ideal size and see how Bontrager helmets are intended to fit.
Learn more| Size | S | M | L | XL |
|---|---|---|---|---|
| Circumference | 51-57 cm | 54-60 cm | 58-63 cm | 60-66 cm |
| Fit system | BOA® | BOA® | BOA® | BOA® |
| Pad material | Moisture wicking pads | Moisture wicking pads | Moisture wicking pads | Moisture wicking pads |
| Buckle type | Standard buckle | Standard buckle | Standard buckle | Standard buckle |
| Includes | Crash Replacement Guarantee | Crash Replacement Guarantee | Crash Replacement Guarantee | Crash Replacement Guarantee |
| Weight | 350g | 380g | 430g | 435g |