Exterior Components› Car and Truck Covers

BAK

BAK RAIL ASSEMBLY SET MODEL 121

$347.23

SKU: B002 RAILS-448121

Special Order
Special Order
Ships in 4–6 weeks
Free Shipping
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Easy — 1–2 hours

Description

The BAKFlip MX4 (GEN 3) is an upgraded hard-folding truck bed cover featuring heavy-duty aluminum matte finish panels for superior UV and scratch resistance and an enhanced premium density foam core. It has upgraded latch housing components and an integrated tailgate seal that allows the cover to be closed with the tailgate in either the closed or open position. This all-season truck bed cover is designed for extreme conditions and everyday use, offers a sleek, low-profile, flush-mount design, and comes with a 5-year warranty.

Fitment

Fitment Guaranteed

Don’t gamble
on fit.

Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

BrandBAK
Part NumberB002 RAILS-448121

Videos

How to Install a BAK BakFlip MX4 Tonneau Cover/Truck Bed Cover

How to Install a BAK BakFlip MX4 Tonneau Cover/Truck Bed Cover
How to Install RealTruck BakFlip MX4 (Gen3) Hard Folding Tonneau Cover on a 2024 Ford F-150

How to Install RealTruck BakFlip MX4 (Gen3) Hard Folding Tonneau Cover on a 2024 Ford F-150
How to Install RealTruck BakFlip MX4 (Gen3) Hard Folding Tonneau Cover on a 2024 GMC Sierra

How to Install RealTruck BakFlip MX4 (Gen3) Hard Folding Tonneau Cover on a 2024 GMC Sierra
BAKFLIP MX4: 18 Month Follow-Up

BAKFLIP MX4: 18 Month Follow-Up
New and Improved RealTruck BAKFlip MX4 Hard Folding Tonneau Cover

New and Improved RealTruck BAKFlip MX4 Hard Folding Tonneau Cover
Top Selling Bed Cover Just Got Better | BakFlip MX4 (GEN3) Review

Top Selling Bed Cover Just Got Better | BakFlip MX4 (GEN3) Review
How to Install BAKFlip MX4 Tonneau Cover

How to Install BAKFlip MX4 Tonneau Cover
Mx4 Bakflip Truck Bed Cover Is The Best We’ve Found!

Mx4 Bakflip Truck Bed Cover Is The Best We’ve Found!

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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