Cheerock U-Bolt Roof Box Clamps 85mm 4-Pack — Stainless Steel Mounting Kit with Lock Nuts & Straps

Cheerock 4-pack U-bolt clamps are a complete stainless-steel mounting kit that secures most rooftop cargo boxes with 85mm internal width, including lock nuts, rubber gaskets, back plates and straps for a reliable roof-rack fit.

If you carry a rooftop cargo box, the connection between the box and your vehicle’s crossbars is critical for safety and noise reduction. This Cheerock kit supplies four U-shaped metal bolts plus the accessories you need to fasten a wide range of roof boxes to bars or factory rails. The components are corrosion-resistant and designed to protect vehicle paint while increasing friction and stability under load.

How do these U-bolt clamps attach to my roof box?

Installation is straightforward: the U-bolt passes through the roof box mounting points, the plastic support board aligns beneath the bar, and heavy lock nuts secure the assembly. Rubber washers cushion your car’s finish and reduce vibration-driven noise.

• Inner width 85mm (3.34in) fits many box mounting channels
• Thread center-to-center 90mm (3.54in) for predictable alignment
• 7mm screw diameter for strong, standard fasteners
• Includes 4 rubber washers and 4 plastic support plates for protection

Will these clamps fit my vehicle’s crossbars and roof box?

The kit is engineered for broad compatibility with most aftermarket and factory crossbars, but fit depends on each box’s mounting geometry. Measure the box’s internal mounting width and the space around your bars to confirm compatibility before installing.

• Check that your roof box mounting points match the 85mm inner width
• Confirm 90mm thread center-to-center suits your bolt pattern
• 7mm bolts match common threaded holes used in roof-box fittings
• Use the included straps for extra restraint on irregular installations

How durable and weather-resistant are these clamps?

Made from iron with plastic and rubber components, the parts resist deformation and exposure to road conditions when cared for properly. Rubber gaskets prevent metal-to-paint contact and help maintain grip, while heavy lock nuts keep tension from loosening over time.

• Iron U-bolts for strong, load-bearing performance
• Plastic back plates distribute pressure and protect surfaces
• Rubber washers reduce corrosion risk and prevent scratches
• Lock nuts supplied to maintain secure tension under vibration

How simple is the install and what comes in the box?

Most installations take only a few minutes with basic hand tools and no special drilling—this kit includes everything required for a typical rooftop cargo clamp job. The full accessory set helps ensure you won’t need extra parts during fitting.

• 4x metal U-bolts, 4x plastic support plates and 4x rubber washers
• 8x heavy lock nuts for secure fastening
• 2x straps for added restraint and 1x hole-sealing sticker
• Quick install with commonly available wrenches; no special tools required

Who is this for: The Cheerock 4-pack U-bolt roof box clamps suit drivers who use rooftop cargo carriers and need a compact, affordable mounting solution that protects vehicle finish while increasing stability. It’s ideal for weekend travelers, families who add seasonal storage, or anyone replacing worn or missing fastening hardware. Before purchase, verify your roof box’s internal mounting width and the crossbar geometry to ensure a snug, secure fit.