Herculite XRV Ultra Unidose Refills - Enamel B1 Based on the latest nanofiller technology. In addition to offering improved handling, polishability and wear resistance, Herculite XRV Ultra delivers improved life-like appearance to final restorations by replicating the opalescence and fluorescence of the natural tooth. Non-sticky, non-slumpy formula with great sculptability and adaption to tooth. High mechanical strength