Hollow artificial rock is wide and flat, making it an ideal cover for pond skimmers, septic lids and other unattractive fixtures in your yard. The imitation rock is made of Fiberlite, a durable, all-weather fiberglass composite and coated with exterior-grade acrylics for long-lasting, natural-looking beauty. The material can be drilled with a standard drill, so you can insert a hose or wires for even more options. The imitation boulder’s wind-resistant design helps it stay put. Each faux boulder is hand painted, so each one is unique. Rocks are a blend of tan and gray shades, primarily tan; the degree of tan and gray colors will vary from rocks pictured. Shape (height and width) is uneven for a realistic look; square shape with angled corners and graduated heights on top left and bottom right corners. Highest interior point is 3.75 Inch. Weighs about 9 pounds. NOTE: Interior view of hollow rock is for informational purposes and does not depict this model. Made in USA. 5-year limited warranty.