Ames Super Elasto-Barrier rubber base coat is a water-based dual-rubber coating used primarily for roof and deck waterproofing applications. It also works well as a primer for other Ames products. It flows into cracks and crevices as a liquid and sets up as a durable rubber sealant to seal leaks wherever they occur. With up to 1000% elasticity, it is formulated to renew, reconstruct, revitalize and extend the life of roofs, walls, and decks. Super Elasto-Barrier is UV sensitive and requires top coating. Great for wintertime patch and repair. Top coat during spring.