Brand New Donseal PU440 Polyurethane Concrete Sealant - Non-Sag Caulking for Concrete Expansion Joints & Walls - Ideal for Sidewalk, Driveway & Foundation Sealant BROAD TEMPERATURE RESILIENCE: Donseal PU440 Polyurethane Caulk operates effectively across a temperature range of -40°F to 175°F, suitable for concrete expansion joints. Its moisture-cure process forms an elastic material, ideal for sidewalk applications. MULTIPLE SURFACE COMPATIBILITY: Formulated for a wide array of substrates, Donseal PU440 can seal concrete, wood, gypsum, aluminum, steel, and ceramic surfaces. This makes it a versatile choice for DIY home projects, foundation and sidewalk tasks, offering reliable sealing across diverse materials. VERSATILE USE: Donseal PU440 is suitable for use in dry, wet, and water-filled concrete holes. The anchoring epoxy offers a robust bond not only to concrete, but also to solid and hollow masonry, hard natural stone, as well as solid and porous rock.