Sealing concrete cracks is simple with Concrete Welder in cartridges. Make sure the crack is clean and free of moisture. If there is a lot of water, use a heat lance or torch to make certain the crack is dry. Open cartridge and squeeze Concrete Welder directly into the crack. Use a scraper or straight-edge to smooth the material out. Wipe up any excess material and allow to dry for 30 minutes. Now the crack is filled and ready for use. Roklin’s long-lasting solution is complete with almost no preparation and little drying time.PolyFlex DS Rapid Concrete & Asphalt Crack Repair 21oz. Cartridge Plus Gun Contains: (1) Dual Cartridge side A and side B. (1) Spiral Bell Static Mixer (1) Hand Operated Dual Cartridge Gun (1) SDS Color: Grey