
Genuine Maytronics part · Filters
Combined Filter Basket Assembly with Seal
Part number 9991660-ASSY · UPC 7290119720910 · 1 year part warranty
Genuine Maytronics filter basket assembly with seal for Dolphin M550, Dolphin M600 and Dolphin Explorer E70.
No MSRP published
Out of stock
About this part
What it does and when to replace it.
This genuine Maytronics assembly replaces the robot's combined filter basket and seal. The basket traps debris collected during cleaning.
Compatibility is based on Maytronics' confirmed model list. Poolbots does not currently stock 9991660-ASSY in its own store. Ask Poolbots' pool experts by live chat or phone for help checking fit and dealer pricing.
- Match both your robot's full model name and part number 9991660-ASSY before requesting the replacement.
- Inspect the basket and seal for damage whenever you clean the filter.
Compatibility
Fits these Dolphin robots.
Confirmed by Maytronics' compatibility checker and each robot's own spare-parts list.
Do it yourself
How to replace it at home.
Switch off and unplug the power supply.
Remove the robot from the pool and open the filter compartment.
Remove the old filter basket assembly.
Install the replacement in the same orientation, checking that the seal sits evenly.
Make sure the basket is seated securely, then close the filter compartment.
Step-by-step answers for this kind of part
How do I replace the filter panels on my Dolphin robot?Video15 min
Find your model below, then follow its video and instructions. The panel removal and installation steps vary by filter design.
S50 (Cayman, T15, T25, Active 10, Escape, Encore, E20, E25) & S100 (Advantage, Proteus DX3, Saturn, Echo, Nautilus CC, Active 15, Escape, Liberty 200/300/400)

Step 1Remove the old filter panels
- Lift the filter cover open.
- Take the filter basket out of the robot.
- Press the plastic release at the top of the filter's wide side, then lift out the released panel. The narrow side panels come out easily. The front and back panels are secured with screws, so use a Phillips-head screwdriver to release them.
- Follow the same process for the opposite side panel.
Step 2Install the replacement panels
- Slide a replacement panel into the basket.
- Push the panel against the frame until it clicks into place.
- Fit the other side panel the same way.
- With both panels in position, clip the filter's bottom section back into place.
S200 (E30, Advantage Ultra, Active 20, Quantum, T30, Proteus DX4, Triton PS) / S300 (E35/E35i, Proteus DX5i, Active 30, T35/T45, Premium 40, Explorer E30, E40i, Active 30i, T55i) / S400 (E50i, Active 50, Explorer E50) / Liberty 600

Step 1Remove the old filter panels
- Lift the filter cover open.
- Take the filter basket out of the robot.
- Press the plastic release at the top of the filter's side, then lift out the panel that releases.
- Work through the remaining narrow and wide panels using the same method.
Step 2Install the replacement panels
- Set the bottom edge of a replacement panel into the filter's lower rail.
- Push the panel into the frame so it clips into the filter.
- Press it against the frame until you hear it click.
- Fit each remaining narrow and wide panel the same way.
Premier/Dx4 (Bag filter)

Filter bag setup for Dolphin Premier
- Turn the robot upside down so you can reach the filter area.
- Release the clips underneath the filter assembly.
- Lift the assembly out of the robot.
- If the white filter screen is not already fitted, secure it with the two screws.
- Check that the filter bag sits securely on the assembly's guard rails.
- Put the filter bag assembly back in, following the guide and video.
Filter cartridge assembly setup for Dolphin Premier
- Turn the robot upside down so you can reach the filter area.
- Release the clips underneath the filter assembly.
- Lift the assembly out of the robot.
- Make sure the white filter screen is not installed for this setup.
- Follow the guide and video to reinstall the assembly.
- Fasten the clips underneath the assembly to secure it.
M250 (Dx3, Nautilus CC Plus)

Step 1Prepare the filter cartridges
- Lift the filter covers and take the cartridges out of the robot.
- Release the clips at the top of each cartridge.
- Inspect the non-return flap for debris.
- Check that the frame is clean before fitting replacement panels.
Step 2Fit the replacement panels
- Seat the locating tabs along the bottom of each panel in the matching grooves on the base frame.
M400/M500 (Sigma, Nautilus CC Supreme, Aquarius XL, Oasis)

Step 1Prepare the filter cartridges
- Lift the filter covers and take the cartridges out of the robot.
- Release the clips at the top of each cartridge.
- Inspect the non-return flap for debris.
- Check that the frame is clean before fitting replacement panels.
Step 2Fit the replacement panels
- Seat the locating tabs along the bottom of each panel in the matching grooves on the base frame.
M600/M700 (Active 60, E60i, Premium 60, Explorer E70)

Step 1Remove the old filter panels
- Lift the filter cover open.
- Take the filter basket out of the robot.
- Press the plastic release at the top of the filter's side, then lift out the panel that releases.
- Work through the remaining narrow and wide panels using the same method.
Step 2Install the replacement panels
- Set the bottom edge of a replacement panel into the filter's lower rail.
- Push the panel into the frame so it clips into the filter.
- Press it against the frame until you hear it click.
- Fit each remaining narrow and wide panel the same way.
Replacement panels and filter care
You can purchase replacement filter panels from Poolbots. Before ordering, confirm that the panel part number matches your robot. For help choosing the correct panels, contact Poolbots' pool experts by live chat or phone.
Additional references:
Specifications
Size & Dimension
- Package Dimensions
- 10.8x7.2x8.6 inch
- Gross Weight
- 1.764 lb
General Info
- Warranty (years)
- 1
- UPC
- 7290119720910
Questions
Combined Filter Basket Assembly with Seal, answered.
Which Dolphin robots fit this filter basket?
Maytronics confirms compatibility with Dolphin Nautilus Titan, Dolphin M550, Dolphin Premium 60, Dolphin M600, Dolphin Active 60, Dolphin T60 and Dolphin Explorer E70.
Does Poolbots stock 9991660-ASSY, and what does it cost?
Poolbots does not currently stock this part in its own store. There is no published list price; pricing is dealer-set. Ask Poolbots' pool experts by live chat or phone for pricing help.
What warranty is listed for this part?
The listed warranty for this replacement part is 1 year.
















