BAKFlip MX4 vs Revolver X4s: Which to Buy? (November 2026)

On this page (9 sections)

1. Which cover opens and stores more easily?
2. Which cover fits your truck?
3. Which cover locks down better?
4. How much bed access do you get?
5. How do the covers handle weather and daily use?
6. How do installation and weight compare?
7. Who should buy the Revolver X4s?
8. Who should buy the BAKFlip MX4?
9. Verdict: which cover should you buy?

Pick the Revolver X4s if you want full bed access with the rear window left clear; pick the BAKFlip MX4 if you want folding panels that lock themselves when closed. The BAKFlip MX4 vs Revolver X4s decision comes down to how each cover opens and stores, not to which brand name sounds tougher.

Both are hard covers from BAK. The real split is folding panels versus a rolling bundle against the cab.

Here is how the two families line up in this BAKFlip MX4 vs Revolver X4s comparison, including which truck beds each one fits.

Which cover opens and stores more easily?

The Revolver X4s rolls with one hand and stores tight against the cab; the BAKFlip MX4 folds in stacked panels toward the cab. The better fit depends on how often you open the cover and what you carry.

The X4s is a hard rolling cover. Its aluminum slats are wrapped in industrial-grade vinyl, and BAK says you pull down on the tailgate cable to open and roll it with one hand.

When open, it rolls forward and fastens against the cab with a strap and buckle.

The MX4 is a hard tri-fold. You fold its panels back toward the cab and secure the stack.

BAK says you can drive with the cover fully open after folding it, so the bed stays usable between stops.

The trade-off is height. A rolled bundle sits low against the cab, while a folded panel stack stands taller.

If you carry tall cargo near the cab, the roll-up leaves more vertical room.

If you load the bed several times a day, the one-hand roll is quicker than folding and latching panels. If you mostly open the cover once a trip and leave it closed otherwise, the folding design is no trouble.

What stays on the truck when the cover is open?

Both designs leave their rails mounted on the bed sides. The X4s rolls its cover material onto those rails, and the MX4 folds its panels above them.

That means neither gives you a completely bare bed. The difference is how much room the open cover takes up above the rails and near the cab.

Which cover fits your truck?

The Revolver X4s fits the Silverado/Sierra and Ram 1500 in this comparison; the BAKFlip MX4 fits the F-150 and the Super Duty. Check your cab and bed length before you order either one.

Here is the fit for each cover in this comparison:

The fit is the first thing to settle. A cover built for one bed length won't adapt to another, so confirm your truck's cab and bed before comparing anything else.

The Silverado/Sierra X4s also works with the MultiPro and Flex tailgates on trucks without the Carbon Pro bed. That matters because the tailgate design changes how the cover closes at the back.

If your truck isn't on this list, you'll need the matching version of the same cover rather than a different size. Our guide on which tonneau cover should I buy helps you start from your truck instead of from the brand.

Which cover locks down better?

The BAKFlip MX4 auto-latches when you close it, while the Revolver X4s locks along the full bed length with its rotational locking system. Both lock at the tailgate, so your bed security depends on the tailgate staying shut.

BAK says the MX4's upgraded auto-latch locking system secures the cover automatically when closed. The maker also says the new lock components resist tampering and forced entry.

That's a maker claim, so treat it as a design goal rather than a promise about theft.

The X4s uses BAK's patented rotational locking system. BAK says it secures the cover along the entire length of the bed on both sides when closed.

That spreads the locking points rather than relying on one spot.

Both designs lock through the tailgate. If someone can open your tailgate, the cover's security depends on the rest of the truck's locking system.

The auto-latch on the MX4 is the easier habit to build. You close the cover and it locks without a separate step.

The X4s takes a deliberate pull to release and a roll to close.

If you park in busy lots and want the cover locked every time without thinking about it, the MX4's auto-latch suits you. If you want locking pressure spread down both bed rails, the X4s design makes that its focus.

How much bed access do you get?

Both covers give you full access to the bed when open; the difference is how much room the open cover leaves you. A roll-up frees more space near the cab, while a folded stack takes up more height.

The X4s rolls smoothly and stores tight against the cab. BAK says this gives full access to the bed without blocking your sightlines through the rearview mirror or your third brake light.

That's a real benefit when you reverse with a load.

The MX4 folds its panels to the cab and BAK says you get 100 percent bed access, whether parked or driving. The folded stack leaves the rest of the bed clear but sits taller than a rolled bundle.

For hauling a tall cabinet or a stack of boxes that reaches the cab, the roll-up leaves more usable height. For everyday loads that stop short of the cab, the folded MX4 stack rarely gets in the way.

Both covers keep the full floor of the bed open when closed. The decision is about the space near the cab, not the floor.

How do the covers handle weather and daily use?

BAK builds both covers for wet weather and daily work, but the materials and seals differ. The MX4 uses aluminum panels with polymer cores; the X4s wraps aluminum slats in vinyl.

The MX4's panels are aluminum with high-density polymer cores. BAK says this generation is 22 percent stronger than the last one.

It also has revised EPDM perimeter seals and tight-fit clamps to keep water out along the bed rails.

The X4s uses industrial-grade vinyl over aluminum black slats. BAK says the matte-black finish runs top to bottom and the cover has newly designed side seals and finished rear corner caps.

The vinyl top gives a smooth surface that sheds water.

Both are matte black. The MX4's matte aluminum finish is hard and panel-like; the X4s vinyl has more of a soft-top look while still being a hard cover underneath.

On upkeep, the vinyl top on the X4s needs cleaning and care over time so it doesn't fade or crack. Aluminum panels on the MX4 are easier to wipe down but show scratches more readily on the finish.

BAK says the MX4 is tested from -40 to 180°F and zero to 95 percent humidity. That's a maker claim about testing, not a guarantee for your climate.

The X4s carries a 5-year guarantee, and so does the MX4.

How do installation and weight compare?

Both covers install on the bed rails with a hardware kit and guide, but the MX4 adds a click-in rail system that BAK says speeds install. Weight is close enough that either needs two people for a careful fit.

The MX4's click-in rail system is new on this generation. BAK says it cuts install time by up to 12 percent.

That's a modest saving, but it helps if you're fitting the cover in a driveway.

The X4s ships with a tonneau cover, hardware kit and install guide. The rails mount to the bed and the cover rolls onto them.

The X4s weighs about 81 pounds. Have a second person help lift either cover onto the truck, because a cover that size is awkward to handle alone and the rails need to line up evenly on both sides.

The BAKFlip MX4 review for the F-150 covers the install and daily use in more detail if you're leaning toward the folding design.

Who should buy the Revolver X4s?

Buy the Revolver X4s if you want a hard cover that rolls out of the way with one hand and leaves your rear view clear. It's the better fit for drivers who load the bed often and carry tall items near the cab.

The X4s suits Silverado/Sierra owners who want the MultiPro or Flex tailgate to keep working with the cover closed. The Ram 1500 version brings the same roll-up design to that truck.

The roll-up bundle keeps sightlines clear when the cover is open. That's useful if you reverse often or tow a trailer and want the third brake light visible.

The trade-off is the vinyl top. It needs regular cleaning to stay in good shape, and the cover rolls rather than folds, so the rails stay on the bed.

Pick the X4s if quick open-and-close and full rear visibility matter more to you than folding panels. It's also the better pick for tall cargo near the cab.

Who should buy the BAKFlip MX4?

Buy the BAKFlip MX4 if you want folding panels that lock themselves when closed and you drive an F-150 or Super Duty. It's the better fit for drivers who leave the cover closed most of the time and want security without a separate locking step.

The F-150 version fits 2021-2026 trucks, including the Raptor and Lightning. The Super Duty version covers 2017-2026 F-250 and F-350 trucks with the 6 ft 10 in bed.

The auto-latch is the feature that sets it apart. Close the cover and it locks without you doing anything extra.

The revised seals and tight-fit clamps also help keep water out along the rails.

The MX4's folded stack sits taller than a rolled bundle. That's the main trade-off if you often carry tall loads that reach the cab.

If you're also weighing the MX4 against another folding cover, our comparison of the BAKFlip MX4 vs Rough Country covers the differences there.

Verdict: which cover should you buy?

The Revolver X4s wins overall for most readers because it scores higher and rolls tight against the cab with one hand. It keeps your rear view clear, gives full bed access and suits the Silverado/Sierra and Ram 1500 beds in this comparison.

The BAKFlip MX4 is the better pick for two groups. F-150 owners who want folding panels and auto-latch security should choose the MX4.

Super Duty owners with the longer bed should choose the MX4 version built for their truck.

If you load the bed often or carry tall cargo near the cab, the X4s roll-up leaves more room. If you close the cover and forget it, the MX4's auto-latch is the easier habit.

Check your truck's cab and bed length first. Then decide between folding panels and a rolling bundle, and the BAKFlip MX4 vs Revolver X4s choice becomes simple.

Frequently asked questions

Is the BAKFlip MX4 or the Revolver X4s better?

The Revolver X4s is the better overall pick because it scores higher and rolls tight against the cab with one hand. The BAKFlip MX4 is the better choice if you want folding panels that lock themselves when closed and you drive an F-150 or Super Duty.

What is the main difference between the BAKFlip MX4 and the Revolver X4s?

The MX4 is a hard folding cover that stacks its panels toward the cab, while the X4s is a hard rolling cover that rolls into a bundle against the cab. Both keep the bed usable and lock at the tailgate, but they open and store in different ways.

Does either cover block the rear window when open?

The Revolver X4s is designed to roll against the cab without blocking your sightlines or third brake light. The BAKFlip MX4 folds to the cab as stacked panels, so the open cover sits higher at the back of the cab.

Can you drive with either cover fully open?

BAK says the BAKFlip MX4 lets you drive with the cover fully open after you fold and secure it. The Revolver X4s uses a strap and buckle to hold the rolled cover against the cab, so check the instructions for your truck before driving that way.