Sika Sikaflex 221 Multi-Purpose Polyurethane Sealant/Adhesive - 10.3oz (300ml) Cartridge - White

Sikaflex® 221 is a premium multi-purpose polyurethane sealant and adhesive designed to provide strong, lasting bonds and elastic seals for a variety of marine and boating applications. Its robust formulation ensures durability and flexibility, making it an ideal choice for maintaining the integrity of your vessel.

Product Description

Sikaflex® 221 is a high-quality, non-sag polyurethane sealant and adhesive that cures upon exposure to atmospheric humidity, forming a durable elastomer. It meets ASTM C920 Type S specifications and is tested and classified by ANSI/UL 723 for surface burning characteristics, ensuring safety and reliability in marine environments.

Key Features

• Highly elastic and long-lasting, accommodating vessel movements
• Resistant to aging, UV radiation, and harsh weather conditions
• Non-corrosive, protecting metal surfaces from degradation
• Can be sanded and overpainted for seamless finishes
• NSF-registered for use with Proprietary Substances and Nonfood Compounds (available in black, grey, and white)
• UL listed for potable water applications (available in black, grey, and white)

Applications

Sikaflex® 221 bonds effectively to a wide range of substrates commonly found in marine settings, making it versatile for numerous sealing and bonding tasks:

• Wood: Ideal for sealing wooden decks and cabins
• Metals: Suitable for bonding and sealing various metal components
• Metal Primers and Paint Coatings: Compatible with 2-component systems for enhanced adhesion
• Ceramic Materials: Perfect for sealing tiles and other ceramic fixtures
• Plastics: Bonds well with different types of plastic materials used in marine equipment

Specifications

Product	Sikaflex® 221 Multi-Purpose Polyurethane Sealant/Adhesive
Package Size	10.3oz (300ml) Cartridge
Color	White (also available in black and grey)
Cure Time	Initial Set: 30 minutes Full Cure: 7 days
Temperature Range	-30°F to +200°F (-34°C to +93°C)
Compliance	ASTM C920 Type S, ANSI/UL 723

Safety Information

WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings.ca.gov.

Additional Resources

Download the Quick Guide (PDF)

Orders of physical products placed by 3 PM EST M-F typically ships the same day, if all requested items are in stock. Weekend orders will typically ship on Monday.

Shipping takes 2-7 days.

We currently ship to the Contiguous 48 States.

Life of Sailing merch is custom made for the customer after an order is placed. Total turnaround is typically 7-14 days from order to doorstep.