Sikaflex 291 310ml – Marine Adhesive & Sealant Cartridge (Polyurethane)

Get professional-grade sealing and bonding performance with Sikaflex 291 310ml—a trusted marine adhesive and sealant cartridge designed for boatbuilding, maintenance, and repair applications.

This one-component polyurethane sealant cures with atmospheric moisture to form a durable, flexible, and waterproof elastomer, making it ideal for marine environments where movement and vibration are constant.

Supplied in a 310ml cartridge, it is designed for use with a standard caulking gun, allowing precise and efficient application for larger jobs and installations.

Sikaflex 291 offers excellent adhesion to a wide range of common marine materials including fibreglass (GRP), wood, metals, painted surfaces, and plastics, ensuring a strong and reliable bond across multiple applications.

Its permanently elastic properties allow it to absorb shock, vibration, and hull movement without cracking or failing—making it ideal for sealing deck fittings, hull joints, and structural components.

Designed specifically for marine use, it is UV, saltwater, and weather resistant, ensuring long-term durability in harsh NZ conditions.

Key Features

• 310ml cartridge – suits standard caulking guns for easy application
• Marine-grade polyurethane sealant – designed for boats
• Flexible & vibration-resistant – won’t crack under movement
• Excellent adhesion – bonds GRP, wood, metal & plastics
• Waterproof & weather-resistant – ideal for marine environments
• UV resistant – long-lasting outdoor performance
• Paintable & sandable – professional finish
• Low odour & non-corrosive – safe for marine materials

Specifications

• Brand: Sika
• Product Type: Marine adhesive & sealant
• Base: 1-component polyurethane
• Cure Type: Moisture curing
• Size: 310ml cartridge 
• Colours Available: Black, White
• Application: Sealing, bedding, light bonding
• Use: Interior & exterior marine applications

Ideal Applications

• Sealing deck fittings and hardware
• Bedding hatches, windows, and ports
• Hull joints and structural sealing
• General marine maintenance and repairs

Sikaflex 291 is one of the most widely used marine sealants due to its versatility, reliability, and ease of application.

Why Buy from Barton Marine NZ?

• Trusted NZ marine supplier
• Fast nationwide delivery
• Genuine Sika marine-grade products
• Ideal for DIY and professional marine use

Pro Tip 

For best results:

• Use a caulking gun for smooth, controlled application
• Apply to clean, dry, grease-free surfaces
• Mask edges for clean lines and remove tape before full cure