AJDHDGA Universal Roof Box U-Bolt Clamps Kit — 4 U-Bolts, 8 Lock Nuts, Fits Rails up to 85 mm, Galvanized

AJDHDGA Universal Roof Box U-Bolt Clamps are a complete mounting kit that secures most roof boxes and cargo racks to vehicle rails using four galvanized U-bolts, rubber gaskets, plastic backing plates, eight lock nuts and two straps.

Whether you're fitting a new roof box or replacing worn hardware, this kit is designed to attach a variety of cargo shells and roof racks to crossbars up to 85 mm wide. Built from corrosion-resistant galvanized steel with rubber washers and plastic back plates, the set reduces abrasion on vehicle paint and increases grip on curved or flat rails. The package includes everything needed for a straightforward install and comes with a one-year warranty and customer support.

How do these U-bolt clamps attach a roof box to different rail types?

These U-bolt clamps wrap around round, square or slightly profiled rails and fasten to the roof box’s base using the included lock nuts and backing plates. Rubber washers cushion the metal-to-metal contact, reducing movement and protecting paintwork. The plastic back plates spread load across the contact area to prevent local pressure points.

• Fits crossbars and rails up to 85 mm wide
• Galvanized steel U-bolts resist rust in wet climates
• Rubber gaskets reduce vibration and protect paint
• Plastic support plates distribute clamping force evenly

Can I install this kit myself, and what tools are required?

Yes — the kit is made for DIY installation with no special skills needed. Typically you need a wrench or socket set to tighten the lock nuts and a screwdriver if your roof box has captive fasteners. The U-bolts are sized and supplied with long enough straps to allow for easy positioning before final tightening.

• Hand tools only: wrench/socket set recommended
• Pre-assembled parts make placement straightforward
• Clearances and strap length accommodate most installs
• Instructions and customer support available for questions

What durability and protection features keep the mount secure?

The clamps combine galvanized steel with rubber and plastic components to balance strength and surface protection. Galvanization slows corrosion from road salt and moisture, while rubber washers and plastic plates guard vehicle finishes and reduce loosening caused by vibration. High-performance lock nuts provide a firm hold under load.

• Galvanized finish for corrosion resistance
• Rubber washers prevent scratches and dampen vibration
• Plastic plates increase bearing area and grip
• Eight lock nuts for redundant, secure fastening

What comes in the package and what if I need help?

The kit contains four U-bolts, four rubber washers, four plastic support plates, eight lock nuts, two straps and one sticker. All parts are inspected before shipping and AJDHDGA offers a one-year warranty plus responsive customer service for installation or fit questions. If a part is missing or you have fitment concerns, contact support for assistance within the warranty period.

• 4 galvanized U-bolts and 8 lock nuts included
• 4 rubber washers and 4 plastic support plates
• 2 adjustable straps for temporary positioning
• 1-year warranty and customer support response within 12 hours

Who is this for: This AJDHDGA mounting kit is suited for drivers who need a reliable, low-cost solution to mount a roof box or replace worn clamps on cars, vans and SUVs. It’s ideal for weekend travelers, tradespeople who use rooftop cargo, and anyone seeking durable, paint-safe hardware compatible with a wide variety of crossbars and rails.