The West System 404 High Density Filler Additive is suited for the toughest of bonding applications. With its high-density formulation, this filler additive is perfect for applications that require superior strength and durability. It is specifically engineered to mix easily with the epoxy products from West System delivering a smooth, easily workable paste that sets very hard. This versatile additive can be used for bonding, filleting, gap filling, lamination and hardware installation.
Recommended Applications
- For creating tough laminations in both wood and composites
- Filling and fairing both above and below the waterline
- Installation of hardware pads
- Creating threaded screw pockets
- Fiberglass repairs
- Marine and autobody repairs





