05203 Marine Adhesive Sealant, White Polyurethane, 3 Oz

3M 5200 Marine Adhesive Sealant is a one-component, high-strength polyurethane formulated for permanent bonding and sealing in demanding marine environments. This moisture-curing sealant bonds wood, gelcoat, and fiberglass, creating a firm, rubbery, waterproof seal on joints and boat hardware both above and below the waterline. A trusted product throughout the marine industry for over 50 years, it handles everything from small porthole repairs to large hull seams with equal reliability.

Whether you're sealing fiberglass deck to hull, installing through-hull fittings, mounting motors on fiberglass transoms, or repairing portholes and deck fittings, this sealant withstands harsh marine conditions and salty spray. The compact 3 oz tube fits easily in a toolbox or glove compartment for convenient storage and on-the-water repairs.

Features and Benefits

• High-Strength Bonding: One-component formula that cures to form a permanent, waterproof seal without shrinkage.
• Flexible and Durable: Remains flexible after curing, allowing for structural movement and absorbing stress from shock, vibration, swelling, or shrinking.
• Weather and Salt Water Resistant: Excellent resistance to weathering, salt spray, and marine conditions ensures long-lasting performance.
• Non-Sagging Formula: Will not sag or flow in vertical or horizontal seams, delivering a clean and professional finish on deck fittings and hull seams.
• Easy Application: Workable with a manual caulking gun, trowel, or spatula for up to 4 hours after application; becomes tack-free in 48 hours and fully cures in 5 to 7 days.

Specifications

• Brand: 3M
• Model: 05203
• Size: 3 oz tube
• Color: White
• Type: Polyurethane marine adhesive sealant
• Moisture-curing, one-component formula
• Gap-filling polyurethane
• Suitable for wood, gelcoat, and fiberglass bonding