High Density Filler-43 oz.
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You have 30 days to request a return. All sale items are final sale.
WEST SYSTEM 404 High-Density Adhesive Filler is an epoxy thickening additive for building maximum-strength, high-cyclic hardware bonds. It also works as a high-strength filleting and gap-filling compound, curing to an off-white color.
Key Features
- Epoxy thickening additive designed for maximum physical properties in hardware bonding where high cyclic loads are anticipated.
- Use for filleting and gap filling when maximum strength is necessary.
- Cures to an off-white color.
Intended Use
- Marine hardware bonding repairs
- Structural epoxy bonding and patching
- Epoxy fillets in boat repair and fabrication
- Gap filling with thickened epoxy mixes
Product Details
- Product name: High Density Filler-43 oz.
- SKU (Shopify variant): 655-40445
- Packaging size: 43 oz
- Color after cure: Off-White
Parts Desk Insights
Best Use Case: Best for making thickened epoxy “high-density” mixes that stay non-slumping and add strength to hardware bonds, fillets, and gap-filling areas.
Common Issues: Common results vary if you don’t mix thoroughly into the epoxy resin/hardener and apply the correct consistency; for best outcomes, follow the epoxy system’s mixing and application guidance and confirm you’re using the high-density (adhesive) filler rather than a low-density fairing filler.
Related Products & Accessories
- Browse WEST SYSTEM fillers & additives - Explore related epoxy fillers and maintenance items in the store.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 1-3 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.