ISOFLEX High-Performance Liquid Rubber Waterproofing Roof Seal Black 2.1 Litre NEW. 2.1 Litre Sealed. Upgrade your roof's protection with ISOFLEX High-Performance Liquid Rubber Waterproofing Roof Seal in sleek black. Designed for durability and efficiency, this 2.1L sealant is the ideal choice for professionals and DIY enthusiasts looking to maintain the integrity of their roof paint sealant. Crafted for versatility, the product's origins remain unspecified, assuring you of its quality and reliability. Whether you're responding to a leak or preventing one from occurring, ISOFLEX offers a robust solution that stands the test of time and weather.