The cuprinol ultra tough wood filler natural 250g delivers professional-grade restoration for damaged wooden surfaces in both interior and exterior applications. Engineered to address wet rot damage and major joinery repairs, this solvent-based formula hardens by chemical reaction to ensure lasting structural integrity. This weather-resistant filler seamlessly fills knot holes, screw holes, and nail holes, preparing surfaces for varnishing, painting or staining. The fast-setting composition remains workable for up to 10 minutes and dries within 30 minutes, enabling rapid project progression. Once cured, the non-shrinking formula resists splitting and cracking while providing good adhesion to sound wood. The hardened surface can be sanded, drilled, screwed and nailed, offering complete versatility for subsequent finishing and construction work. Features & benefits: repairs wet rot damage and suitable for major joinery repairs in indoor and outdoor applications. Fast-setting composition workable for up to 10 minutes and dries within 30 minutes. Non-shrinking formula with good adhesion resists splitting and cracking for long-lasting, weather-resistant repairs. Can be sanded, drilled, screwed and nailed when dry for complete finishing flexibility. Fills knot holes, screw holes, and nail holes prior to varnishing, painting or staining. Solvent-based formula hardens by chemical reaction for lasting durability. Colour: natural. Size: 250g.