Maytronics Robotic Pool Cleaner Replacement Cork For Inner Wheel Tube Manufacturer Part # 9982275 Fits the Following Cleaners: Dolphin Nautilus Plus Dolphin Nautilus Dolphin Triton Dolphin Triton Plus Dolphin M200 Dolphin M400 Dolphin C3 Cb Dolphin C4 Cb Dolphin Discovery Dolphin Saturn Dolphin Edge Dolphin Endeavor Dolphin Supreme M3 Dolphin Supreme M4 Dolphin Supreme M5 Pentair Prowler 820 Pentair Prowler 830