1.5″ to Fines or SB2 Limestone is a graded aggregate blend of stone dust up to 1″ crushed limestone. It compacts tightly for a strong, durable base, making it ideal for roads, driveways, parking lots, and under concrete or asphalt. Designed to meet state DOT specifications, this material provides excellent stability and drainage. Uses: Road base • Driveways • Parking lots • Under asphalt or concrete