West System C209SA Extra Slow Hardener, 315 ml (10.6 oz.)
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You have 30 days to request a return. All sale items are final sale.
The West System C209SA Extra Slow Hardener is designed for use with West System 105 Epoxy Resin in hot, humid, or high-temperature conditions where standard hardeners cure too quickly. It provides approximately twice the working time of the 206 Slow Hardener, making it well-suited for warm-weather bonding, coating, and laminating applications where extended open time is needed.
At a 3:1 mix ratio (resin to hardener by volume), the C209SA cures to a clear, amber-coloured solid. Compatible with the West System 300 Mini Pump for accurate metering. This 315 ml (10.6 oz.) size is ideal for smaller repairs and single-use projects.
Cure Schedule
- Pot life: 15–20 minutes at 95°F (35°C) / 50–60 minutes at 70°F (21°C)
- Solid state: 6–8 hours at 95°F / 20–24 hours at 70°F
- Full cure: 4–9 days additional curing after solid state
- Maximum pot life: adequate up to 110°F (43°C)
Key Features
- Extra slow cure for hot, humid, or high-temperature conditions
- Approximately 2× the working time of 206 Slow Hardener
- Mix ratio: 3:1 (resin to hardener by volume)
- Cures to a clear, amber-coloured solid
- Compatible with West System 300 Mini Pump for accurate metering
Available Sizes
- West System C209SA Extra Slow Hardener – 315 ml (10.6 oz.) — this product
- West System C209SB Extra Slow Hardener – 1.24 L (42.2 oz.) — mid-size for larger projects
- West System C209SC Extra Slow Hardener – 5.3 L (1.4 Gallon) — bulk size for large or ongoing work
Related Products
- West System C205 Fast Hardener – 208 ml (7 oz.) — faster cure option for cooler conditions
- West System C207SA Special Clear Hardener – 315 ml (10.6 oz.) — clear finish option in the same size
- West System G/Flex 650-K Aluminum Boat Repair Kit — flexible epoxy repair alternative
Parts Desk Insights
Best Use Case: The C209SA is the right starting point for customers who need extra slow cure for a one-off warm-weather repair or small bonding job and don’t need a large quantity. It’s the smallest size in the C209 Extra Slow family — ideal for DIY boaters doing seasonal maintenance in summer conditions. Always confirm the customer is using West System 105 Resin, as this hardener is not a standalone product. For larger projects or professional shop use, direct them to the C209SB (1.24 L) or C209SC (5.3 L) for better value per litre.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.