Book end your whitening routine with Pro Whitening Boost & Extend. Our advanced before and after whitening enhancers help you get the most from every whitening treatment. All you do is just add whitening. These 2 steps, when combined with your regular whitening routine help to maximize your whitening results and lock in your brightest smile by preventing new stains from forming. First, ProActivate™ Whitening Accelerator preps teeth to increase brightness by 65%.1 Next, you whiten with any SmileDirectClub Premium Teeth Whitening product to whiten up to 9 shades in 1 week.2 After, ProLong Whitening Extender protects and prolongs results, preventing new stains from forming. By pre-whitening, you boost results 65%1 with ProActivate™ Whitening Accelerator. Then post-whitening, you prevent new stains from forming with ProLong™ Whitening Extender. All you need to do is add whitening. When combined with SmileDirectClub Premium Teeth Whitening gel or Fast-dissolving Whitening Strips, your whitening regimen can brighten your smile up to 9 shades in 1 week.1 Both products are low-sensitivity, enamel-safe and approved to use for up to 14 days straight, within the treatment guidelines of most teeth whiteners. The pack includes enough of each whitening enhancer for 2 complete treatments.