Root Reboot is a longer-lasting demi-permanent gray coverage solution that will last up to two weeks. Whereas, The Great Cover Up Root Touch Up & Brow filler is designed as a quick fix that will last 1-2 days, and is sweat, rain and pillow proof, and washes out with your next shampoo. They go hand in hand. We recommend starting with Root Reboot, and touch up with The Great Cover Up if grays do appear a few days before your next color appointment.