This ground cloth is custom-sized to fit underneath your Black DiamondHiLight tent to extend the life of the tent floor. Sized to prevent water from pooling underneath the tent. High-quality, densely woven, coated black nylon is used for longevity and to decrease drying time. Reinforced grommets along the sides let you easily use the ground cloth as a tarp. Ground cloth adds approximately 10 ounces to your pack, depending on tent model.