DYNAFLEX 230® – Tough, Flexible, and Built to Last. Get the strength of silicone with the ease of latex. DYNAFLEX 230® delivers a long-lasting, flexible seal that moves with your home — no cracks, no gaps. 100% waterproof, weatherproof, and UV-resistant, it keeps out moisture, mould, and mildew for lasting protection. Perfect for sealing around windows, doors, and trim — inside or out. Paint-ready in just 2 hours, DYNAFLEX 230® is the go-to sealant for pros and DIYers who demand performance that lasts.