BAKFlip MX4 Gen 4 Hard Folding Tonneau Cover
Our MX4 Gen 4 sets the standard for hard folding tonneau covers with premium aluminum construction and a sleek matte black finish. This fourth-generation design features our proprietary FRP (Fiber Reinforced Polymer) panels that resist dents, UV damage, and extreme weather while maintaining a low-profile stance that complements your truck's lines.
We engineered the Gen 4 with an advanced dual-action tailgate seal and integrated drain channels that route water away from your cargo. The cover folds completely open for full bed access or locks in the closed position to protect valuables. Installation takes just 30 minutes with our clamp-on rail system—no drilling required.
- Premium matte black aluminum panels with Fiber Reinforced Polymer core
- Low-profile design sits flush with bed rails (under 3 inches)
- Dual-action tailgate seal with enhanced drain channel system
- Folds flat against cab for 100% bed access
- Clamp-on installation—no drilling into truck bed
Premium Materials & Weather Protection
We build every BAKFlip MX4 Gen 4 panel with aircraft-grade aluminum bonded to a dense FRP core that delivers superior strength without the weight penalty of solid metal. This construction resists impacts that would dent traditional covers while the factory-applied matte black powder coat finish protects against UV rays and road chemicals.
The Gen 4 introduces our most advanced water management system yet. Integrated drain tubes route moisture through the rail system and away from your bed, while dual EPDM rubber seals create a weatherproof barrier at the tailgate. We’ve tested this cover in freezing rain, desert heat, and high-speed highway conditions to ensure your cargo stays dry regardless of climate.
Installation & Compatibility
Our patented clamp-on rail system mounts directly to your bed rails in under 30 minutes with basic hand tools. The Gen 4 design accommodates most factory stake pocket configurations and works with spray-in bed liners up to 1/4 inch thick.
Truck Bed Fit
We manufacture application-specific models for all major truck brands and bed lengths. The MX4 Gen 4 fits 5.5-foot, 6.5-foot, and 8-foot beds depending on your truck model. Our design maintains full access to factory tie-down points and doesn’t interfere with cab-mounted accessories or fifth-wheel prep packages when folded open.
Operation & Bed Access
The four-panel folding design gives you complete control over bed access. Fold one section for access to the front third of your bed, two sections for hauling longer items, or flip all panels against the cab for a completely open bed. Each panel weighs just 12-15 pounds and operates with smooth gas-strut-assisted hinges.
Our dual-position locking system secures the cover in the closed position at the tailgate or allows you to lock panels against the cab when hauling tall cargo. The rotary latches engage with stainless steel strikers that won’t rust or seize over time. We include two keys with every cover—one for the latch and one for the optional lock cylinder at the tailgate.
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What people are saying
Common questions about the MX4 Gen 4
Yes, the MX4 Gen 4 clamp system accommodates most spray-in liners up to 1/4 inch thick including Line-X and Rhino Liner. The clamps adjust to grip the bed rail securely regardless of liner thickness. For thicker liners or drop-in bedliners, we recommend contacting our fitment team to confirm compatibility with your specific truck model.
Water that hits the cover flows to integrated channels along each hinge line and drains into tubes routed through the side rails. These drain tubes exit behind the cab or near the tailgate depending on your truck model, directing water away from the bed. The dual-action tailgate seal creates a barrier that prevents water from entering through the rear gate even during pressure washing or heavy rain.
Yes, you can safely drive with the panels folded against the cab and secured in the upright position. We recommend using the included strap system to prevent panels from shifting during highway driving. Many customers drive with panels open when hauling tall cargo that extends above the bed rails.
The Gen 4 features an improved drain channel design with larger-diameter tubes, upgraded EPDM seals at the tailgate, and reinforced hinge plates for smoother operation. We also refined the clamp geometry for better compatibility with newer truck bed rail designs. The core panel construction and warranty remain the same between generations.
The MX4 Gen 4 folds completely flat against the cab, providing full bed access for fifth-wheel installation and operation. You can tow with the cover folded open without any interference. For trucks with factory fifth-wheel prep packages, the cover installs normally and doesn't block access to stake pocket mounts.
The MX4 Gen 4 sits less than 3 inches above the bed rail surface when closed, which translates to minimal cargo height loss inside the bed. The clamp-on rails add approximately 1 inch to each side rail. Most customers report they can still fit standard toolboxes and cargo organizers without clearance issues.
While the MX4 Gen 4 supports up to 400 pounds of static weight, we don't recommend aftermarket rack systems that require drilling through the panels. For customers who need rack capability, we offer our CS/F1 model that integrates a factory rack system designed to work with the folding panel structure. You can mount lightweight cargo carriers using strap-on systems if needed.