Tankless Reverse Osmosis System with small size, replacement filter once a year - Waterdrop D4

Easy Installation, Intelligent Filter System, Brushed Nickel Faucet
Regular price €238,80
Sale price €238,80 Regular price

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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.

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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.

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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.

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

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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, 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.

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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, 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

Thank you for shopping at Waterdrop. We appreciate your decision to purchase our products and aim to ensure a rewarding experience throughout your exploration, evaluation, and purchase process.

Order Cancellations:

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

1. If you contact us within 24 hours of purchase:

Since most orders ship the same day, kindly email us at contact or call us at (888)-352-3558 within 24 hours of placing the order. There will be no cancellation fees for standard items canceled before shipment. If the package has already been shipped, we will provide a prepaid label for return, and once we receive the package from you, we will issue a refund.

2. If you contact us after 24 hours of purchase:

  • In such cases, you will need to bear the shipping fee if the package is already shipped (subject to our system status, not the order status).
  • The product must be damage-free, packed in the original packaging we sent to you, and returned with the original receipt of purchase.
  • We will process your refund after receiving the package.

30-day Risk-free Return Policy:

  • You are eligible to return any item* within 30 days of receipt.
  • All returned items must be disassembled and repackaged as they were originally received.
  • The 30-day risk-free return policy applies to all item*.
  • No restocking fee will be charged, but customers are responsible for the return shipping cost. We will cover the return postage expenses in the case of any return requests related to a quality issue.
  • Please note that the 30-day risk-free return policy is only valid for orders* within the continental United States.

Return after 30 Days of Receipt:

  • You may still return any item after 30 days of receipt.
  • In this case, customers are responsible for the return shipping cost. The total cost of shipping will be deducted from your refund.
  • All returned items must be disassembled and repackaged as they were originally received.
  • A 10% restocking fee will be applied to all returned products. However, in the event of any return requests related to a quality issue, we offer free returns or replacement with a new product.

1-year Warranty:

Enjoy peace of mind and confidence in your purchase with our 1-year warranty, backed by lifetime technical support.

If you receive a damaged item and wish to file a claim, please email with your order information and a picture of the damaged or incorrect product. We are eager to assist you.

For products that become defective during the warranty period due to a quality issue, rather than your own breakage or misuse, we can accept a free return, provide free repair service, or issue a new replacement.

Exchange Policy:

1. Defective Products:

If you receive a product with quality issues or damages, please contact our customer service team within 30 days of receipt. We will provide you with a free exchange service. Please provide order information and photos of the damaged product when contacting our customer service team for better assistance.

2. Non-Quality Issues:

If you wish to exchange a product for non-quality-related reasons, please note the following:

  • The product must be within 30 days of purchase and unused.
  • The product must be returned in its original packaging, along with the original purchase receipt.
  • You will be responsible for the re-shipping costs.
  • Please note that the exchange policy is only applicable to orders made on the official

How to Return a Product?

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

Step 1: Contact our customer service team before returning a product. We will respond with return instructions within 24 hours.

How to contact us:


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

Step 2: Prepare the package after receiving confirmation from the customer service team, and please note the following requirements:

  • Include the order number in the package. You can print out the order detail page or leave a note inside the package.
  • Ensure the package contains the original receipt of purchase.
  • Return the product in the original packaging we provided.
  • The product must be damage-free (this does not apply to defective products, as damage will void the refund).

Step 3: Contact our customer service and provide your return tracking number. We will track the package and process your refund within 5 working days after receiving and inspecting the package.

General Information for All Returns:

1. Defective Products:

If you receive a product with quality issues or damages, please contact our customer service team. we provide free returns, replacement with a new product, and comprehensive technical support.

2. Non-Quality Issues:

  • You are responsible for shipping the products to the return address provided.
  • Returned items will undergo inspection before issuing a refund.
  • Refunds will be processed within 5 working days after the item has been inspected, and it may take 4-7 days to be reflected in your credit card statement.
  • We highly recommend using a traceable and insurable shipping method for your return. We are not responsible for returns lost or damaged in transit, and you will need to file a shipping claim.
  • Please note that orders made via 3rd-party sellers, including Amazon, are not eligible for our return policy.
  • All returned items must be disassembled and repackaged as they were originally received. Items returned in a condition other than "like new" will be subject to a 10% restocking fee to cover repairs or part replacement. The restocking fee will be deducted from your refund.

Return Address:

Ecolife Technologies, Inc.

1951 S Lynx Pl,

Ontario, CA 91761

United States

Tel: 888-352-3558

Price Match Policy:

At Waterdrop, we highly value our customers' shopping experience. That's why we offer a 30-day price match guarantee. If you happen to notice a price reduction on the item you purchased at within 30 days of your purchase, you are eligible to claim a price-match refund. To request a refund, please contact us at We are here to assist you promptly.

Note: This Waterdrop price-change refund policy only applies to items shipped and sold by If you're buying from a different vendor, you'll need to contact that seller if the price drops.

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Tankless Reverse Osmosis System with small size, replacement filter once a year - Waterdrop D4

Regular price €238,80
Sale price €238,80 Regular price
Model number
Product dimensions
16.02 x 6.22 x 12.44 inches
Rated voltage/ Frequency
110-120V/ 60HZ
Rated power
Service flow rate
0.28 gal/min
Feed water pressure
14.5-87 psi
Feed water requirement
Municipal tap water
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 Water Filtration System 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 system 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.

What are the advantages of Waterdrop reverse osmosis systems?

When you buy the Waterdrop D4 reverse osmosis water filtration system, you are meeting the need for pure water in your household while adding to the beauty of your interior. The artistically designed housing houses an innovative technology that delivers an excellent filtration performance by combining multiple filtration materials into a single composite filter.
You only need limited space to install this tankless reverse osmosis system. Its optimized filtration performance means it reduces heavy metals, chlorine, and even TDS. This system packs a powerful filtration performance and an ultra-extended service life despite having a single composite filter.
With just one filter replacement all year long, this Waterdrop reverse osmosis water filter will serve you with maximum convenience.

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.

What is the flow rate of this reverse osmosis water filtration system?

This Waterdrop reverse osmosis system can deliver 0.28 gallons of water in a minute, conveniently meeting your household water needs.

Does Waterdrop whole 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 to install the reverse osmosis home system?

The simple design ensures an easy installation. You can be done in less than 30 minutes without needing any external help. All you have to do is check the instruction manual, and if you encounter any problem, watch the installation video on YouTube.

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?

a. Please note that the water softener is NOT designed to provide drinkable water. Its main function is to soften the water for washing clothes, taking a bath, flushing toilets, etc.

b. If a salt-based water softener is installed BEFORE the RO unit:
-The filtered water could be salty since our unit can only remove 90% salt added by the softener.
-The RO filter's lifetime could be shortened due to the unusual amount of sodium in the source water, which is NOT covered by the warranty.
-We have already put a clear warning on the product page regarding this aspect.

c. If your water softener is NOT salt-based, then our RO unit should work properly with it.

Can I use this reverse osmosis system in my RV?

Yes, this reverse osmosis water filtration system can work with your RV. It has an integrated design that makes it possible to install it even in a tiny under-sink space, such as RVs. You can combine this filter system with your RV for a regular and reliable supply of clean water.
Now you can stop using the dirty and unsafe water from campgrounds. This filter system ensures you get clean and pure water for drinking directly from your taps and shower. You are also immune to the common health issues associated with contaminated water, which may prevent you from enjoying your road trip.

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

We do not recommend using well water as source for our RO systems.
The reasons are as follows:
1. Large particles.
Compared to municipal tap water, the well water is rich of large particles, which will clog the filters easily, and shorten their lifetime significantly.Please note that the filters will still need to be replaced more frequently, even if you have added a pre-filtration system.
2. Composition
The well water has very complicated compostion, and some of them (apart from the large particles) can cause the filter or internal valve to be clogged and prevent the RO system from normal performance.
3. Water pressure
The well water may not provide the feed water pressure that the RO system requires (14.5 psi min.). Furthermore, the water pressure will be even lower after passing through pre-filtration systems.

Do I need to have an electrical outlet under my sink for this work?

Yes, the system requires electricity to work. So, an electrical outlet is necessary.

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.

What does Pure to Drain Rate mean?

The reverse osmosis water filter relies on a semi-permeable membrane to filter out impurities from drinking water. When the tap water is compressed through the RO membrane, it produced pure water and waste water. The ratio of pure water to waste water is called wastewater ratio. 1:1 wastewater ratio means 1 gallon water is wasted per 1 gallon purified, and 2:1 wastewater ratio means 1 gallon water is wasted per 2 gallon purified. The higher the wastewater ratio is, the less waster water produced during the filtration process. During the use of RO water filter, the actual ratio might be lower than the labeled, depending on many factors such as water quality, pH, pressure and temperature.
Upgraded 6 Stages Filtration
Upgraded 6 Stages Filtration
6-in-1 filter, filter layer by layer, the filtration accuracy is only 0.0001μm. Reduce 1000+ harmful substances in water to ensure the health of drinking water for you and your family.
Filtered Water Increased By 300%
1:1 drain ratio, compared with the traditional RO machines, it can filter up to 300% more purified water, make efficient use of water resources, and save your water bills
Filtered Water Increased By 300%
Quick Replacement, Convenient Life
Quick Replacement, Convenient Life
The intimate buzzer reminds you to replace the filter, you only need to replace it once a year with a push-and-pull, which you can easily operate it at home.
*We do not recommend using well water as source for our RO systems. We do not recommend directly connecting tankless RO to a refrigerator or ice maker. You can connect the RO system to the refrigerator or ice maker with Waterdrop PMT small water pressure tank >.
Fast, Stable, Long-Lasting With 400 GPD
The water output is more rapid, stable and durable. It only takes 12 sec to fill glass of water, which can meet the water needs of the whole household.
Fast, Stable, Long-Lasting With 400 GPD
Compact Design, Save More Undersink Space
Compact Design, Save More Undersink Space
With the composite filter and compact design, the height of this reverse osmosis system is only 12.44-inch, saving more undersink space.
Perfect For Small Spaces
  • Exquisite body, suitable for small spaces, can also be used in RVs without worry, enjoy pure water with our RO water filter system everywhere.
  • Perfect For Small Spaces
    No Noise, Quieter Life
    No Noise, Quieter Life
    Quieter than a laptop when working. You can barely hear no noise closing the door. Rest assured to enjoy a peaceful life.
    No Leaking Risk
    Advanced integral water way with no leaking points. This tankless reverse osmosis system keeps you away from safety risks and protect your family always.
    No Leaking Risk
    Cleaner Filter, More Intelligent
    Cleaner Filter, More Intelligent
    Automatic flushing of filter and water lines. Even if you go out for a short period of 24 hours, you can drink fresh and purified water at home, bringing you pure enjoyment at any time.

    D4 RO Filtration System

    D6 RO Filtration System

    D6 RO Filtration System

    G3P800 RO Filtration System

    G3P800 RO Filtration System

    G3 RO Filtration System

    G3 RO Filtration System

    G2P600 RO Filtration System

    G2P600 RO Filtration System

    G2MNR RO Filtration System

    G2MNR RO Filtration System

    Need Installation
    Beneficial Minerals × × × × ×
    Flow Rate 400 GPD 600 GPD 800 GPD 400 GPD 600 GPD 400 GPD
    Pure to Drain Rate
    Drain ratio stands for the ratio of wastewater and purified water dispensed by a RO system. For example, the 3:1 drain ratio means it uses up a gallon of wastewater for every 3 gallons of pure water you get.
    Pure to Drain Rate Pure to Drain Rate Pure to Drain Rate Pure to Drain Rate Pure to Drain Rate Pure to Drain Rate
    Faucet Ordinary faucet Smart faucet Smart faucet Smart faucet Ordinary faucet Ordinary faucet
    Display Filter lifespan Filter lifespan & TDS Filter lifespan & TDS Filter lifespan & TDS Filter lifespan Filter lifespan
    Self-clean × ×
    Holiday mode × × ×
    Electricity Required
    Filter Cartridges WD-D4RF







    Noise(≤) 55dB 55dB 65dB 65dB 55dB 55dB
    Filter Lifespan 12 Mths 12 Mths CF-6 Mths
    CB-12 Mths
    RO-24 Mths
    CF-6 Mths
    CB-12 Mths
    RO-24 Mths
    CF-12 Mths
    P6MRO-24 Mths
    MNR-12 Mths
    CF-12 Mths
    MRO-24 Mths
    Dimensions(inch) 16.02*6.22*12.44 15.98*5.98*11.97 18.11*5.67*17.72 18.11*5.67*17.72 17.32*5.91*13.9 17.32*5.91*13.9
    WD-D4RF Filter for Waterdrop D4 Reverse Osmosis System
    WD-D4RF Filter for Waterdrop D4 Reverse Osmosis System
    • The reverse osmosis filter has a 1-year service life, protecting you from water hazards for the entire year.
    • You can replace the water filter in 3 seconds with a single twist. No tools are required.
    Total price: $99.99
    Total price: $99.99
    Remineralization Filter
    Remineralization Filter for All Series Waterdrop Reverse Osmosis Systems-Waterdrop MNR35
    • An excellent add-on Remineralization filter adopts 18 natural materials to restore minerals.
    • Saves 8300 single-used bottles and $12600 spent on bottled mineral water.
    • Compatible with RO water system, undersink filtration systems and refrigerator.
    Total price: $29.99
    Total price: $29.99