UnderCover UltraFlex Vs. BAKflip MX4

Updated on May 5, 2025

RealTruck Expert Team
Written by
 RealTruck Expert Team
Frank Bisciotti
Edited by Frank Bisciotti
Comparison of truck bed covers: Undercover Ultraflex versus Bakflip MX4.

Two of the most popular hard folding covers available, the UnderCover UltraFlex and the BAKFlip MX4, stand out in the world of hard-folding tonneaus. Built to last in the USA, both tonneau covers offers superior features.

Shared Features

A closed bottle with a cap.

Hard Folding Folds toward the truck's bulkhead.

Lock icon on a gray background.

Locks with Tailgate Must unlock and open tailgate to open cover.

Shield emblem with a cross in the center.

Aluminum Construction Made of corrosion-resistant aluminum.

A person typing on a laptop at a desk with a notebook and coffee cup.

Matte Black Finish Matches most OE bed rail caps.

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Dual-Action Tailgate Seal Cover can be shut whether the tailgate is open or closed.

UnderCover UltraFlex

Folds Straight Up

Woman adjusting equipment on a truck bed in a desert landscape.

The UltraFlex folds up to your truck's bulkhead area where it is held straight up in place with prop rods. It does not contact your truck's cab.

Carpeted Lower Panels

A close-up of a black panel mounted with an antenna or cable attached.

The lower panels of the UltraFlex are lined with a carpet-like material.

VIDEO: UnderCover UltraFlex Tonneau Cover Product Review

BAKFlip MX4

Folds Against Cab

Man installing or inspecting a gear compartment on a pickup truck outdoors.

The MX4 folds all the way back against your truck's cab on foam rubber bumpers, ensuring third brake light visibility on short and standard truck beds.

Black Lower Panels

Close-up of a sliding metal roof rack on a vehicle with a textured surface and wiring attached.

The lower panels of the MX4 are finished in black powder coating.

VIDEO: BAKFlip MX4 Tonneau Cover Features and Benefits

Have questions? Contact our product experts.

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