This is a Maytronics 6101611-R4 package of 4 Climbing Brush Rings for specific Dolphin Robotic Pool Cleaners. This includes 2×2, Heavy-Duty, DX3/4, DX6, Deluxe 4, 3001, Supreme M3/M4/M5, Nautilus, DLX4/5, Apollo, Endeavor, Atlantis, Atlantis Basic, Triton, Edge, Spectra Light, Quest, Wave 65/90, Supreme M5, Apollo Plus, Saturn, Deluxe 5, Primal X3, M400/M500, DX3S, Apollo Windo, Triton Plus. It is also designed for Pentair Prowler 820/830 pool cleaners.
Please review the schematics under Found in the Following Products for a full list of cleaners the brush rings will fit.