Techniseal® HP NextGel Jointing Sand is a state-of-the-art mix of graded sand (astm-c144) and binder that flows smoothly down joints for a fast and effective installation of pavers or slabs with false or wide joints. It is also recommended for surfaces exposed to heavy traffic and for high-humidity areas. Easy to use, nextgel™ jointing sand starts to set only a few minutes after being activated with water and quickly becomes resistant to water erosion (rain, splashes, sprinklers, etc.). Nextgel™ jointing sand offers great resistance to weed growth, insect invasion and erosion.