GE Metal Silicone 2 Sealant, Metallic Grey, 10.1oz. From the #1 Silicone Brand, Metal Silicone 2 sealantisahigh-performance, 100%siliconeand100% waterproofsealant ideal for a range of metal projects. Common uses include repairing and sealing sheds, siding, gutters, recreational vehicle parts, roofs and vents. This 30-minute rain-ready formula is metallic gray in color and offers excellent adhesionand permanent flexibility with 10-year mold-free product protection to help resist mold and mildewgrowth. Backed by a lifetime guarantee.