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The Fox Mainframe MIPS is a trail ready helmet that brings the safety features from Fox’s high-end helmets to riders of all experience levels. Extended coverage in the rear of the helmet protects riders from impacts to the back of the head, without adding excessive bulk. This helmet incorporates MIPS technology, which disperses rotational forces during impacts, better protecting the brain and still maintaining a comfortably lightweight form. The Mainframe provides some of the best venting capability of helmets in this category, with large vents at the front and rear keeping things cool by optimizing airflow over the head, making those tough climbs just a bit easier. The Mainframe is a capable, comfortable helmet for new riders and expert shredders alike.
| Core Material | Molded EPS foam |
|---|---|
| Closure system | Clip |
| Intended Use | Trail, XC |
| Weight | 390g (size medium) |
| Size | Small | Medium | Large |
|---|---|---|---|
| Head Circumference (in) | 20.1" - 21.7" | 21.7" - 23.2"" | 23.2" - 24.8" |
| Head Circumference (cm) | 51cm - 55cm | 55 - 59cm | 59 - 63cm |
CALIFORNIA PROPOSITION 65 WARNING: This product can expose you to chemicals including (Cadmium, Phthalates, Bisphenol, Nickel (Metallic), di(2-ethylhexyl)phthalate "DEHP"), which is known to the State of California to cause cancer and/or cause birth defects or other reproductive harm. For more information, go to www.P65Warnings.ca.gov.
Most items SHIP SAME DAY if ordered by 3pm PST and FREE SHIPPING on orders over $50. Please note that oversize charges may still apply on some heavy or large items and free shipping does not apply to PO Boxes.
1-day free standard Shipping on most orders to California, 2-day free standard Shipping on most orders to Nevada, Arizona, & Utah. Other states can expect delivery within 3 to 5 days.
Jenson USA ships worldwide, including APO/FPO addresses. For a more specific shipping quote and transit time estimate, simply add the items you are interested into your shopping cart and look for the "Shipping Options" box at the top of the cart page. You don't have to login or create an account to see shipping charges and time in transit estimates.
Some manufacturers restrict where we can ship their products. If this item has shipping restrictions, they are listed below. If you'd like to buy an item that we cannot ship to your address, we can accept your foreign credit card and ship it to a US address for you.
We strive to get you the gear you want at a competitive price. If you find an item we offer from a competitor at a lower price, let us know. We will do our best to instantly match their price. To qualify for the Price Match, your purchase must meet the following conditions:
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All helmets aren't created equally and when it comes to your brain, it doesn't pay to be cheap. If there is one thing that you should absolutely never pinch pennies on, it is your helmet. There are many helmets out there from brands who haven't done proper testing that lack safety features in order to be the least expensive consumers. There are also affordable options out there that are packed full of safety features that you might not have known existed.
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There are so many different avenues that you can take to purchase a new bike, so what sets us apart from them? Why buy a bike from us?
Here at Jenson USA, we take great pride in making sure that your bike buying experience is confidence inspiring and trouble-free from start to finish. We want to be absolutely sure that we are providing the best possible service we can to each and every one of our customers so that there are no questions when purchasing a new bike from us!
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With Bike Park season officially kicking off all across the world, we thought it might be a good idea to put together a video discussing some of the best full face helmets for 2023.
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At Jenson USA, it's important to us to support those who are helping build the community of riders and sharing their experiences with others. To that end, we've built an arsenal of Ambassadors that we help to support.
These ambassadors are the pedal-pounding aficionados, building a following of fellow riders across social platforms; they're the lifeblood of our cycling community. Their stories inspire, their passions unites – Their the glue that binds us all. Meet some of the Ambassador crew.
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ANGi is a helmet-mounted sensor that measures the forces transmitted to your helmet during a crash, as well as the harmful rotational forces that occur during crashes when your helmet doesn't actually impact the ground. Head into our informational blog article to learn all about this innovative safety tech for your rides.
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CALIFORNIA PROPOSITION 65 WARNING: This product can expose you to chemicals including (Cadmium, Phthalates, Bisphenol, Nickel (Metallic), di(2-ethylhexyl)phthalate "DEHP"), which is known to the State of California to cause cancer and/or cause birth defects or other reproductive harm. For more information, go to 