Get free shipping, on most items, with your $50 purchase today! Same day shipping on most orders if placed by 3pm PST.
This offer is only available to physical shipping addresses in the 48 continental United States (no PO Boxes), and some exclusions apply.
Some large and/or heavy items are subject to additional oversize charges that are separate from standard shipping costs.
Bike Build Process
All bikes are built, tested, tuned, and ready to ride upon shipment. The bike build process typically takes 2-3 days to complete depending on the bike model and the complexity of the build.
Orders for in-stock items placed by 3PM PST usually ship on the same day. Orders that include special-order or backordered items may be subject to shipping delays depending on product availability. Refer to estimated delivery times in cart when selecting shipping options.
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:
Price Matches may only be honored on identical items. The product must be the same make and model (i.e., the same size, color, year, etc.).
The identical items must be in stock and ready for immediate delivery at the competing dealer.
Price Matching voids any currently advertised Jenson USA promotions or special offers (i.e. free shipping, free headset...). If the competitor offers free shipping on the specific item, Jenson USA will still match the price and free shipping offer.
The product must be brand new. We do not Price Match refurbished or used items.
Our Price Match Policy is valid only for qualified Internet retailers.
The competing dealer must be an authorized US retailer for the brand. This means that the manufacturer lists this dealer as an authorized and official retail web site.
The competing online retailer's principle business must be located within the United States.
Our Price Match Policy does not combine with any competitor’s coupons, rebates, promotional offers, or product-combo deals on your order.
Some items may not be eligible for price match due to manufacturer pricing requirements.
The Price Match Policy is subject to change at any time.
If you have any questions regarding a Price Match, one of our Gear Advisors will be happy to lend you expert guidance via phone, email, or chat.
Price Matches made post-purchase will be refunded via gift card
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.
MIPS Technology reduces rotational forces during a crash
Extra coverage on the back of the head
Lightweight at only 390 grams (size M)
Moisture-wicking liner can be removed and washed
Molded EPS foam
390g (size medium)
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.
Q & A
Jenson USA ships worldwide, including APO/FPO addresses. For a quote, simply add the items you are interested in to your shopping cart and look for the "Shipping Options" box. You don't have to login or create an account to see shipping charges.
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 preferred address, we can accept your foreign credit card and ship to a USA address for you.
Get free 1-day California shipping with your $60 purchase today, on most orders. Please note this offer is only available to physical shipping addresses in California(no PO Boxes), and oversize charges still apply on some heavy/large items
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