The Gray Long Timing Track is a two pack replacement set for Maytronics Dolphin Cleaners. The tracks are for specific cleaners including Dolphin Nautilus, Dolphin Triton, Dolphin Triton Plus, Dolphin Wave 50, Dolphin Wave 75, Dolphin Wave 90, Dolphin Wave 2X2 Gyro, Dolphin Quest, Dolphin Premier, Dolphin Apollo Plus, Dolphin Discovery, Dolphin Advantage Plus RC, Dolphin DX6, Dolphin M4, Dolphin M5, Dolphin Edge, and Dolphin 9985006-R2.