Maytronics Ultra Fine Cartridge-Lg | 9991425-R4
Maytronics
SKU: 9991425-R4
Maytronics 9991425-R4 Ultra-Fine Filter Panels (4 Pack, Medium) for Dolphin Robotic Pool Cleaners | Genuine Replacement
The Maytronics 9991425-R4 is a genuine Dolphin ultra-fine replacement filter panel kit that includes 4 medium-size filter panels. These ultra-fine panels are designed to capture very small debris such as dust, silt, sand, and other fine particles to help improve water clarity and maintain robotic cleaner performance.
Key Features
- Part number: 9991425-R4
- Brand: Maytronics (Dolphin genuine part)
- Product type: Ultra-fine replacement filter panels / cartridge panels
- Quantity: 4 panels (4-pack)
- Size/style: Medium panel set (commonly listed)
- Filtration type: Ultra-fine debris capture
- Maytronics certified genuine replacement part
- Commonly listed warranty: 1 year (seller/manufacturer listing dependent)
What This Part Does
- Replaces worn, clogged, or damaged filter panels in compatible Dolphin robotic cleaners
- Captures ultra-fine debris for improved water clarity
- Helps maintain filtration performance and debris retention during cleaning cycles
- Supports easier routine maintenance with removable, rinseable panel filters
Common Compatibility Notes (Verify Before Ordering)
- Used on select Dolphin robotic pool cleaners that use the medium cartridge panel system
- Compatibility varies by cleaner model and production version
- Some models may require a conversion kit if the cleaner originally used a filter bag system
- Always verify your exact cleaner model and existing filter panel part number before ordering
Important Notes
- This is an ultra-fine filter set, which is ideal for small particles but may load up faster in heavy leaf debris conditions.
- For best performance, rinse after each cycle (or more often during dusty/sandy conditions).
- Confirm your cleaner uses the medium 4-panel cartridge style before purchase.
Use & Care Notes
- Install all panels correctly in the filter basket/frame according to your Dolphin cleaner manual.
- Rinse thoroughly with a hose after each cleaning cycle.
- Do not allow debris to dry and harden in the filter media.
- Inspect panel frames and media regularly for cracks, tears, or deformation.
- Keep a spare set on hand for faster cleaning turnaround during peak season.
Related Products (Aqua Pool Supply)
- Maytronics 9991425-R4 Ultra-Fine Filter Panels (Search)
- Dolphin Filter Panels & Cartridges (Search)
- Maytronics 9991414-R1 Conversion Kit (Search)
- Dolphin Premier Parts (Search)
- Dolphin Triton Parts (Search)
Maintenance Tips
- Rinse panels immediately after use to prevent fine debris from packing into the filter media.
- Rotate between two panel sets to reduce downtime and extend filter life.
- Inspect for debris bypass and make sure all panels are seated properly.
- Replace panels when filtration performance drops or the media/frame becomes damaged.
Questions about returns? View our return policy.
Hours Of Operation:
Monday - Friday: 7:00 am to 5:00 pm Phoenix Time
Saturday: 8:00 am to 2:00 pm
Sunday: Closed
- We do not ship on Saturday or Sunday.
- Orders totaling more than $300 will require signature confirmation upon delivery.
- We process and prepare orders for shipment within 1 business day. Please note that many other pool supply retailers require 3–5 days of handling time before shipping.
- Orders placed after 1:00 pm Phoenix Time may not be eligible for same-day shipment.
- Expedited shipping options are available at checkout.
Return Policy:
- Products that are received damaged will receive a refund in store credit.
- Most products are eligible for return within 30 days of receipt, except where noted below.
- To initiate a return, please complete an RMA form prior to sending your item back.
- Original shipping costs are non-refundable and will be deducted from the return credit.
- Items returned missing accessories or original packaging, or that are not in the same condition as received, may be subject to a restocking fee of up to 100% depending on the condition of the item upon return.
- Some returns will be charged an automatic 15% restocking fee.
- We are unable to issue refunds for items that have been damaged or rendered inoperable due to installer error.
- Please complete the return form to receive your RMA number and return shipping label.
- Chemical products are not eligible for return under any circumstances.
- The Pentair Colorsync 618031 is not eligible for return.
- Pool cleaners are not eligible for return.
- Opened seals and o-rings are not eligible for return.
- Capacitors are not eligible for return.
- Plastic popup tools are not eligible for return.
- Automation components and circuit boards are not eligible for return.
- If a light is returned due to a reported malfunction and is found to be fully operational upon testing, return shipping costs and a restocking fee will be deducted from the refund.
- Orders refused at the time of delivery will be subject to the original shipping costs being deducted from the refund.
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