UnderCover Flex Hard Folding Tonneau Cover for Ford F-250 & F-350 Super Duty (2017-2026), 6'10" Bed
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Warranty Information
Vendor warranty summary
UnderCover Warranty
At a glance: Limited warranty for the original purchaser: 3 years on most covers, 5 years on Ultra Flex, lifetime structure and paint on factory-painted LUX and Elite LX.
This is UnderCover's warranty, not an NVMOS policy. We've summarized it in plain English to save you a search. The manufacturer's official terms always govern and can change without notice. Last reviewed on nvmos.com: November 4, 2026.
Coverage by product line
| UnderCover product | Coverage |
|---|---|
| Ultra Flex (structure, hinges, seals, hardware) | Limited 5 years from retail purchase date |
| Flex (structure, hinges, seals, hardware) | Limited 3 years from retail purchase date |
| Triad (structure, hinges, seals, hardware) | Limited 3 years (product listing notes prorated after 3 years) |
| Select (structure, hinges, seals, hardware) | Limited 3 years from retail purchase date |
| SE and Elite (ABS structure) | Limited 3 years |
| LUX and Elite LX (ABS structure) | Limited lifetime |
| LUX and Elite LX factory paint | Lifetime, against abnormal fading or peeling |
| Gas/hydraulic struts and mounting hardware (one-piece covers) | Limited 1 year |
| SwingCase (ABS structure, lock, hinges, hardware) | Limited 1 year |
What's covered
- Defects in materials and workmanship, starting from the retail purchase date
- Repair or replacement of the defective part at UnderCover's option
- Factory-applied paint on LUX and Elite LX covers that fades or peels faster than the truck's original paint due to a defect
What's not covered
- Owners after the original purchaser; one-piece cover coverage also ends if the cover moves to another truck
- SE, Elite, LUX and Elite LX covers not bought from an authorized dealer
- Neglect, lack of maintenance, abuse, misuse, accidents and weather damage
- Improper installation, modified installation hardware, alterations and added equipment
- Damage from cleaners not labeled safe for rubber (folding covers) or safe for plastics (ABS covers)
- Normal wear and tear
- Driving with or tying down a one-piece cover in the open position, and use in competitive racing
- Paint damage to the truck itself
- Paint not applied at the UnderCover factory, and an exact color match
- Shipping and transportation costs on warranty claims
How to make a UnderCover warranty claim
- Return the product to the place of purchase, or submit a claim online from RealTruck's UnderCover warranty page.
- Provide your order number, name, address, phone and email, vehicle year, make and model, product name or part number and a description of the problem.
- Include a copy of the original receipt and photos of the cover; UnderCover may ask for proof of the defect.
- Do not ship anything back without authorization; unauthorized returns can be refused or sent back at your cost.
UnderCover contact: UnderCover (RealTruck): 877-216-5446; contact form at https://realtruck.com/contact-brands/contact-undercover/ · Warranty page
Bought it from NVMOS? Start with us.
UnderCover's first route for a claim is the place of purchase, and it wants the order number, original receipt and photos, all of which tie back to your NVMOS order. Contact us first and we will put the claim together, get it authorized and handle RealTruck for you. Have your order number and a few photos of the issue ready, then call or text us at (920) 249-7744 or send us a message.
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Disclaimer: The information on this page describes UnderCover's own warranty policy. It is not a warranty offered by NVMOS (No Visible Means of Support LLC). Manufacturers update their terms at any time; we review these pages periodically, but the manufacturer's current official policy is the one that applies to your claim. Sources: UnderCover warranty policy (RealTruck, official) and UnderCover Flex product page (RealTruck, official) and UnderCover Select product page (RealTruck, official) and UnderCover Triad product page (RealTruck, official). Last updated on nvmos.com: November 4, 2026. See our return policy for NVMOS's own terms.
About the brand
UnderCover makes hard tonneau covers, from one-piece ABS lids to tri-fold and rubber-hinged folding covers, and is now one of the RealTruck brands. At NVMOS we carry UnderCover covers cut for the bed lengths of the full-size and midsize pickups we support.
Made in: Assembled in Missouri (per RealTruck's UnderCover product listings) · Lead time: In-stock parts ship in 1-3 business days; parts stocked at the manufacturer take about 1-2 weeks.
Shop all 723 UnderCoverWarrantyAll brands
Warranty terms are set by UnderCover, not NVMOS, and can change. Bought from us? Call (920) 249-7744 and we'll handle the claim with the brand.
UnderCover Flex Hard Folding Tonneau Cover for Ford F-250 & F-350 Super Duty (2017-2026), 6'10" Bed
This UnderCover Flex hard folding tonneau cover fits the Ford F-250 Super Duty (2017-2026) and Ford F-350 Super Duty (2017-2026) with the 6 ft. 10 in. bed (standard, extended and crew cab). It pairs the lockdown of a hard cover with the easy access of a soft one, using FRP composite panels that sit inside the bed rails. It suits drivers who haul tall loads one day and want the bed covered the next.
| Spec | Detail |
|---|---|
| Fitment | Ford F-250 Super Duty (2017-2026); Ford F-350 Super Duty (2017-2026) |
| Bed length | 6 ft. 10 in. |
| Cab | Standard, extended and crew cab |
| Style | Hard folding |
| Finish | Black textured |
| Panels | FRP composite panels |
| Part number | FX21021 |
| Weight | 70 lb |
Measure your bed and confirm it is the 6 ft. 10 in. length before ordering. Installation instructions are available. UnderCover install instructions: download the PDF. Not sure it fits your build? Call or text us at (920) 249-7744 with your year, trim and setup and we will confirm it.
Will it fit my truck?
It fits the Ford F-250 Super Duty (2017-2026) and Ford F-350 Super Duty (2017-2026) with the 6 ft. 10 in. bed (standard, extended and crew cab).
Can I drive with the cover open?
Yes. Built-in prop rods hold it folded so you can drive with the bed fully open.
Do I need tools to remove it?
No. The cover comes off in seconds without tools.
What is the warranty?
See our UnderCover warranty page for the current terms.
Specifications
UnderCover Flex Hard Folding Tonneau Cover for Ford F-250 & F-350 Super Duty (2017-2026), 6'10" Bed FAQs
Will it fit my truck?
It fits the Ford F-250 Super Duty (2017-2026) and Ford F-350 Super Duty (2017-2026) with the 6 ft. 10 in. bed (standard, extended and crew cab).
Can I drive with the cover open?
Yes. Built-in prop rods hold it folded so you can drive with the bed fully open.
Do I need tools to remove it?
No. The cover comes off in seconds without tools.
What is the warranty?
See our UnderCover warranty page for the current terms.
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