Diablo's premium Ultraflex sanding sponges include break-through innovations that improve performance， extend sanding life and increase hand-sanding productivity. Featuring a premium aluminum oxide blend， these foam sponges remove material faster and offer up to 3X longer sanding life versus standard hand sanding sheets. Ultraflex foam technology allows flexible， multi-profile contour sanding in hard to reach areas. The full contact design provides maximum sanding potential by delivering consistent scratch patterns and ultra-smooth finishes. The superior grain bonding system， Endura-Bond， provides Diablo's sanding sponges with longer life and extreme durability.