Quickly and effortlessly create a more dense concrete surface every time with E5® Catalyst. After pouring the slab and using E5® Internal Cure, simply spray on E5® Catalyst prior to combo blades to begin the chemical reaction at the surface. E5® Catalyst reduces drag by producing a micro grout, making troweling smooth and effortless – resulting in less user fatigue and lower cost of equipment maintenance. The result is an extremely hard and dense concrete surface.