Flex Paste is a super thick rubberized paste that you can spread, shape, form, and seal virtually everything. It starts out as a thick paste and dries to a strong, flexible, rubber coating that can be applied to all types of surfaces to seal out air, water, and moisture.It clings to the surface and instantly fills large gaps, cracks, and holes. It wont shrink or wash away and can be painted any color. Can be applied on dry or wet surfaces, even underwater!