
GSA Gap Attack Gap Filler 440g
GSA
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Features
Overview
GSA Gap Attack 440g is the go-to acrylic gap filler for tradies and serious DIYers who want a clean, flexible seal that actually lasts. It pumps into gaps up to 25 mm, stays flexible, resists water and takes paint perfectly—ideal for skirting, architraves, windows, doors or any crack that needs sealing inside or out.
Why You’ll Love It
- Fills big gaps (up to 25 mm) without sagging or shrinking.
- Paintable in 1–2 hours so you can finish the job the same day.
- Water-resistant and flexible—handles movement and weather without cracking.
Built for Real Work
Australian-made premium acrylic formula that guns on smooth and cures tough. Sticks to plaster, brick, timber, masonry and most building surfaces. Once cured it’s mould-resistant and stays put for years—proper sealant that painters and chippies have trusted on thousands of jobs without callbacks.
Perfect For
- Tradies sealing skirting, cornices, window reveals and expansion joints.
- DIYers patching cracks, filling around doors or prepping walls for painting.
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