FibreKleer 4X Tapered Post and Drill Kit: 15 Posts - 5 each of sizes 1.25mm (Black), 1.375mm (Purple), 1.50mm (Green) and 3 Drills - 1 each of sizes 1.25mm, 1.375mm, 1.50mm. Fiber Posts feature outstanding radiopacity of up to 400% of aluminum. Translucent glass fibers bundled in a proprietary clear resin matrix provide outstanding flexural strength and help to preserve the natural lifelike esthetics that are desired when all ceramic restorations are prescribed.