NextStone Slatestone Panel Rocky Mountain Graphite (8 Panels Per Box)(17.12 Sq. Ft. Per Box) Matching Accessories: Sandstone Ledger & Ledger Corner, Window and Door Trim: Graphite Matching Corners: Slatestone Outside Corner Rocky Mountain Graphite Durable and Lightweight. Quality Polyurethane panels cast from real stone Certified Green Product. Easy Installation Energy Savings With Increased R-Value