GE Metal Silicone 2 Sealant- Squeeze, Metallic Gray, 2.8oz. From the #1 Silicone Brand, Metal Silicone 2 sealantÊisÊaÊhigh-performance, 100%ÊsiliconeÊandÊ100% waterproofÊsealant 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 adhesionÊand permanent flexibility with 10-year mold-free product protection to help resist mold and mildewÊgrowth. Backed by a lifetime guarantee.