Flex Paste is a super thick rubberized paste that you can spread, shape, form and seal virtually everything. Starts out as a thick paste and dries to a strong, flexible, rubber coating. It 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 won't shrink or wash away and can be painted any color. Can be applied on dry or wet surfaces, even underwater. The DS-3PKS Putty Knife Set from Allway Tools is perfect for all your scraping surfaces or spreading material in various activities. These knives are strong enough to withstand everything your activities have to offer.