WD-D4RF Filter for Waterdrop D4 Reverse Osmosis System

Replacement for WD-D4-W reverse osmosis filtration system
Regular price $99.99
Sale price $99.99 Regular price
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  • Key Feature
    • [Compatible model] WD-D4-W
    • [Revolutionary filter structure] We adopt an innovative technology and design to integrate different filtration materials into a 6-in-1 composite filter. The reverse osmosis water filter uses the least space to achieve an optimized filtration effect.
    • [Crystal clean water] Highly efficient reverse osmosis filter reduces any impurities larger than 0.0001 microns. With this system, you can count on getting clean, fresh drinking water with improved taste.
    • [Worry-free replacement] Replacing the filter is no difficult task. All you need to do is to open the front cover and pull out the filter. Yes! That simple.
    • [All-year-round excellent performance] The reverse osmosis water filter has a 1-year service life, protecting you from water hazards for the entire year.
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Shipping policy

Shipping rates and delivery estimates

Shipping Method

Estimated Delivery Time


Economy Shipping

4-10 Business Days


Standard Shipping

3-6 Business Days

$5.99(Free on order over $200)

Express Shipping

2-5 Business Days


* Shipping charges for your order will be calculated and displayed at checkout.

* The Delivery Time is calculated based on the shipping date, not the order date. The actual shipping date can be delayed due to invalid shipping address, weekends/holidays, etc.

Handling Time:

We need 24h to 48h to prepare your order, most of the packages will be shipped out within 24 hours except weekends and holidays.

Track your order

Once your order is shipped, you will receive an email from us containing the tracking information. Tracking information is also available in your "Order Details" page.

Shipping areas

The products can be delivered to the most of states in United States except American Samoa, Micronesia, Guam, Marshall Islands, Northern Mariana Islands, Palau, Puerto Rico and U.S. Virgin Islands.

International shipping

We are sorry that the international shipping service is not supported for the time being.

Shipping Carriers

We work with 4 carriers to make sure your order will arrive on time: UPS, USPS, FedEx and Amazon Logistics US.

Delivery Time Exceeded

Shipping might experience delay due to covid-19. If your order is delayed, please contact us via email service@waterdropfilter.com, we will check the situation with the transportation company in time. Thanks for your understanding and support.

Note: We don't accept requests to specify a certain carrier to deliver the package.

Shipping origin

The package will be shipped from one of our US warehouses closest to your location.

* If you have any questions, you can contact our customer via LiveChat or email to service@waterdropfilter.com, we will reply to you as soon as possible!

Sales Tax

The sales tax will be collected in accordance with U.S. tax laws. Customers whose delivery address within the following states will be charged a certain tax at checkout, and the tax rate is determined by the local government. (AZ, CA, CO, FL, GA, IL, IN, KY, MA, MD, MI, MN, NC, NJ, NV, NY, OH, PA, TX, UT, VA, WA, WI) All taxes collected will be reported and filed to the IRS on time.

30-Day Return ×
No Worries Guarantee

Thanks for shopping at Waterdrop. We appreciate the fact that you like to buy the stuff we build. We also want to make sure you have a rewarding experience while you're exploring, evaluating, and purchasing our products.


If you wish to cancel an order, please contact our customer service team

If you contact us within 24 hours of purchase:

We can cancel the order for you at no additional cost. The cancellation may take up to 3 days, thank you for your patience and understanding.

If the package is already shipped, we will issue a prepaid label and return your payment after we have received the package from you.

If you contact us after 24 hours of purchase:

You need to bear the return fee if the package is already shipped (depends on our system, not the order status).

The product has to be damage-free, packed in the packaging we sent to you, and with the original receipt of the purchase.

We will return your payment after we have received the package from you.

There are times when we may not have the product(s) that you choose in-stock or may face some issues with our inventory and quality check. In such cases, we may have to cancel your order. You will be intimated about it in advance so that you do not have to worry unnecessarily about your order.

Return Policy

We accept return reasons including defective, no longer needed, change mind, not as described, etc.

If you want to return the item without any quality issue, you need to bear the return fee yourself and pay 20% of the original order as a restocking fee. We will cover the return postage for return requests regarding quality issue.

Once you received a damaged / incorrect item and you want to file a claim, please email


together with your order information and the picture of the damaged / incorrect product. We are eager to help.

If you would like to return a product, please follow the next guidelines:

Step 1: contact the customer service team before return a product, we will reply you with return tips within 24 hours.

How to contact:

Email: service@waterdropfilter.com

Toll-free Tel: (888)-352-3558

Step 2: prepare package after you get confirmation from customer service team, please be noted the following requirements:

• The order number needs to be included in the package. You can print out the order detail page or leave a note in the package.

• The package needs to come back with the original receipt of the purchase.

• The product has to be in the packaging we sent in the first place.

• The product has to be damage-free (not applicable for defective products), damage on the product will void the refund.

Step 3: Please contact our customer service and send your return tracking number. We will track the package, and refund your money within 5 working days after we receive and check the package .

Return Window

We offer a 30-day return guarantee. Warranty will begin from the date the product is received. If a product grows defective during the warranty period due to a quality issue rather than your own breakage or misuse, we can accept a return, provide free repair service, or issue a new replacement.

Return address:

Ecolife Technologies, Inc.

17910 Ajax Circle

City of Industry, CA 91748

United States

Tel: 888-352-3558

Refund Policy

After receiving your request or your packages, it may take up 1-7 business days to refund your money. (Unfortunately, due to current situations and the COVID-19, your refund may require an additional 3-5 days to process. Thank you for your patience and understanding.)

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WD-D4RF Filter for Waterdrop D4 Reverse Osmosis System

Regular price $99.99
Sale price $99.99 Regular price
Model number
Filter life
Up to 12 months or 1,000 gallons
Feed water pressure
14.5-87 psi
Feed water requirement
Municipal tap water
How to chose your RV water filter?
You need to know your water source and water quality at first.
The key to find a suitable water filter for yourself is to know your local water quality. Most RV sources water from municipal tap water. City water suppliers use chlorine to disinfect municipal water and eliminate waterborne-disease carrying bacteria. However, chlorine can leave water with a chemical taste and smell.
Regardless of the water’s source, if you are in a region of the country with hard water, your RV will be exposed to high levels of calcium and magnesium, which can lead to scale build-up and damaged plumbing.
Waterdrop D4 Reverse Osmosis Filter effectively reduces chlorine, sediments, heavy metals, bacteria, chemicals, viruses and more, basically any impurities larger than 0.0001 micron. That means this filter can also reduce TDS and soften your water sources. This system is one of the best water filter for your RV.
Also in some RV parks, they use local well water as source. Well water can possess high levels of sediment, heavy metals, and potentially bacteria and microorganisms. If so, we suggest you to install a pre-filter, blocking out large particles initially. Pre-filtered water without large particles travels into RV can protect water-related appliances in your RV.

How does reverse osmosis filter work?

The water supply in your home gets in under pressure, irrespective of where you live. Reverse osmosis relies on this same pressure to push water through a semipermeable membrane.
Water passes through the semipermeable membrane under pressure. This leads to the separation of the impurities from the water molecules. The impurities are on one side of the membrane, and the water molecules on the other, with the clean water going to your tap without any impurity whatsoever. There are several filtration stages in the RO water filtration process – up to seven sometimes, and these are responsible for the high purity of water.

Can I drink reverse osmosis water everyday?

Yes, it is perfectly safe to drink reverse osmosis water frequently. There are fewer contaminants in the water, so you are safe. The absence of contaminants means you are not prone to health issues like brain damage or anemic conditions in children. Parasites causing diseases are also eliminated from your water sources, providing you with clean and pure water.

Does Waterdrop wholee house reverse osmosis waste a lot of water?

For a traditional RO system, wastewater production is inevitable. However, the Waterdrop D4 RO purifier is powered by advanced technology that keeps the drain ratio at 1:1. Therefore, you can save up to 300% more water than the tanked traditional filter systems. You also spend less on water bills.

How long does a reverse osmosis filter last?

The integrated filter in this system needs to be replaced once every year.

When to replace the filters of this reverse osmosis system?

You should replace it only once a year, depending on the quality of your local water.

Can I connect a water softener with this reverse osmosis system?

Yes, this reverse osmosis system works flawlessly with a water softener.

Is this reverse osmosis water filtration system suitable for well water?

There are high amounts of sediments in well water, alongside harmful bacteria, microorganisms, and heavy metals. To use this reverse osmosis system with well water, kindly install a pre-filter, which will filter out the large particles at the first line.

Can I connect the remineralization filter with this reverse osmosis water filter?

Yes, this reverse osmosis water filter works perfectly with a remineralization filter. All you have to do is buy a suitable remineralization filter and connect it to the system. Simply search for “Waterdrop Remineralization Filter” and add the filter.
Compatible With Waterdrop D4 Reverse Osmosis Water Filtration System
Model Number: WD-D4RF
Revolutionary Filter Structure
Technology is no longer as complex as it used to be. We adopted innovative technology and design to integrate different filtration materials into a 6-in-1 composite filter after comprehensive research on the properties of various materials. The reverse osmosis water filter uses minimal space to optimize the filtration effect, reducing TDS, chlorine, heavy metals, and more.
Powerful Reverse Osmosis Filtration Layer
The accurate RO membrane features 0.0001 micron pore size, effectively reducing TDS value and contaminants such as harmful chemicals, chlorine, VOCs, lead, mercury, arsenic, copper, etc.
All-Year-Round Performance
This is not a filter that you would have to change often. You need not change it for a whole year, and you would still be assured of excellent performance. The reverse osmosis filter has a 1-year service life, protecting you from water hazards for the entire year.
Effortless Replacement
Replacing the filter is incredibly easy. You only need to open the front cover and pull out the filter. This does not even require much time and energy.