3M Company 6520 Marine Adhesive Sealant 10 Oz White

Product Description

The 3M COMPANY 6520 is a fast-cure marine adhesive sealant designed for demanding above- and below-waterline applications. Supplied in a 10 oz cartridge and available in white, this sealant delivers an extremely strong bond that remains flexible after cure, allowing it to accommodate structural movement without cracking or losing adhesion. It resists weathering and saltwater exposure, making it a reliable choice for sealing, bonding, and bedding tasks in marine environments. Licensed marine technicians and experienced boat builders rely on this product for hull fittings, deck hardware, and other structural joints that require a long-term watertight seal.

This sealant is suited for residential and commercial marine applications where both strength and flexibility are required. Typical uses include sealing through-hull fittings, port frames, hatches, and deck penetrations on fiberglass, wood, and metal substrates. Its fast-cure formulation reduces downtime during installation or repair. The cartridge format is compatible with standard caulking guns, making it straightforward to apply in the field or in a shop setting.

Key Features

• Fast-cure 5200 formulation bonds and seals above and below the waterline
• Extremely strong adhesion that retains strength after full cure
• Stays flexible to absorb structural movement and vibration
• Excellent resistance to saltwater, weathering, and UV exposure
• 10 oz cartridge format for use with standard caulking guns
• White color for clean, finished appearance on light-colored surfaces

Compatibility

Designed as an OEM-style marine adhesive sealant suitable for fiberglass, wood, and metal substrates in above- and below-waterline marine sealing and bonding applications.

Installation Notes

Application should be performed by a qualified marine technician or experienced installer familiar with marine sealant procedures. Surfaces must be clean, dry, and free of oil, grease, and loose material before application. Allow full cure time before submerging the assembly below the waterline. Use appropriate solvent and ventilation practices as directed by the product safety data sheet, and follow applicable marine industry guidelines for structural bonding.

Technical Specifications

• Net Volume: 10 oz
• Color: White
• Package Weight: 12.46 pounds
• Package Quantity: 12 per case
• Unit of Measure: Each
• Container Type: Cartridge

Standard Information

• Brand: 3M COMPANY
• Manufacturer Part Number: 6520