ARDEX K 301™ Exterior Self-Leveling Concrete Finish is a self-leveling primer and finish that expedites the coating and smoothing process for interior and exterior applications over approved and properly prepared concrete and nonporous surfaces, including terrazzo, epoxy coatings, and ceramic and tile. stoneware; above or below grade and at ground level. key features A blend of Portland cements and other hydraulic cements Use to smooth new or existing concrete and approved non-porous surfaces Installs in thicknesses between 1/4” and 3/4” (6 to 18 mm) without aggregate, and up to 2” (5 cm) with aggregate Can be stepped on in 2 or 3 hours Resistant to freezing and thawing Suitable for use in wet areas For commercial, residential and light industrial applications For use in interior and exterior applications Can be installed as a base under ARDEX MC™ Moisture Control Systems Can be used as a base before installing a floor covering standards Tests performed in accordance with ASTM C1708