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Published: February 10, 2024

Waterpik WF-04 Sidekick review

Author: Jon Love (1 Comments)
Waterpik WF-04 Sidekick review 1

Intelligent design for a travel friendly flosser


The Sidekick from Waterpik is an absolutely genius piece of kit, I like it a lot!

It is a balance of power and features whilst remaining portable. For those always on the go, that want the conveniences that come with a corded water flosser, the Sidekick has you covered.

The kicker is the price. It is not a cheap product and I understand why.




Compact & travel friendly


No ability to rotate the tips 360 degrees


Stylish design


No interchangeable flossing tips for specific user needs


Good size tank considering the size of the unit


No timer or pacer


Choose between 5 pressure settings

Which other water flossers should I consider?

The answer to this question is really going to depend on your priorities and lifestyle.

If you want the best water flosser and tend not to travel all that often, then you should consider the Waterpik Aquarius.

If you want something that is portable, but you don’t wish to be restricted by cables, then you will want to take a look at the Waterpik WP-560.

However, if you like the best of both and don’t mind paying for it, then the Sidekick is the one to go for.

Waterpik Cordless Advanced 2.0
Waterpik Cordless Advanced 2.0

Design, usability, clean & general use

Waterpik WF-04 Sidekick review 2

One of the newest products to be launched by Waterpik there is a definite feeling and sensation of premium with this product.

As I write in the price section of this review, the Sidekick is certainly not cheap, but from the moment you unbox it, you kind of see why.

Given the overall size of the unit, I was surprised by how large the actual box was, but this is part of the experience and premium feeling you get. The unboxing process is almost like a grand reveal.

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I have listed above what you get in the box, but essentially you get all you need and not much more.

It is the black with copper model I have bought to test and it looks fantastic.

Whilst I knew the unit would be small, it is not until you get hands-on do you appreciate the size and quality of the product.

The base unit is the brains of the operation if you like. Inside this is the pump and electronics that draws the water from the reservoir that sits on top and feeds it out through the detachable handle.

I have included a list of the dimensions at the end of this review, but to give some context to the size, the base unit is about as wide as a CD case or a postcard.

It is a little wider than it is tall. It has a bit of weight to it and feels solid.

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4 rubber feet help keep it in place on a countertop.

Plastic is the main construction material, the majority is all black with the copper accents being reserved for the top edge of the unit, the power button, Waterpik logo and the ring on the top of the flosser handle.

The power button is large and slightly concave and sits centrally on the top of the unit.

On the front is the Waterpik logo and what could be mistaken for a power button, but is actually the release button for the handle/hose that clips in to the right hand side.

The hose is fixed into the handle, but detaches from the base unit.

The right hand side of the unit itself has a slider that allows you to adjust the pressure of the water flow. There are 5 different pressure settings.

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The whole concept here is about portability and convenience.

Ingenious design means the power brick/adapter actually pulls out from the base of the unit and tucks back in securely for transportation.

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The reservoir is large enough that the base unit slides inside it when transported.

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Somewhat separate is the cable that fits to the power brick and runs between it and the base unit to deliver the power.

All these items fit nicely into the provided soft touch travel case which is the size of a small washbag.

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When in the travel case, whilst it is not really small and compact it is the best example I have seen when it comes to a portable water flosser.

Cordless water flossers are generally appealing for travelers, but they tend still to be quite bulky and rounded. The unit has a lot of soft sweeping curves to it, but when all packed away it is a squarer and more convenient shape for transportation.

Whilst it still might not tick the box for the backpacker, for a regular traveler or those going away on vacation for a couple of weeks with a suitcase, this is by no means bulky and should fit happily in most people's luggage.

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When all pieces together and connected to the power it looks much like a small version of any regular countertop water flosser.

The power cable runs from the back of the unit and is approximately 3.9ft (47 inches/120cm) and the hose on the handle 3.2ft (39 inches/100cm).

It is worth noting whilst it is a US 2 pin power adapter, it has support for 100-240v, so international travelers need only a plug adapter and not a voltage converter.

When all setup and ready to go, there is no place for the hose to tuck into like there is on many other units, but it comes out the box very tightly coiled.

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For those who need the length of the hose, you may have to fight a little with it to release some of the tension installed in the coiling.

The back of the handle had a clip, which allows it to attach/rest on the edge of the reservoir.

13oz or 400ml is the capacity of the water tank. There are no measurements on the plastic unit, but it is enough to get 60 seconds or so of flossing time.

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This is one of the biggest draws about this unit.

Many of the cordless options have smaller tanks and it can be a struggle to complete an interdental clean without needing to refill the reservoir.

With the Sidekick, you can floss knowing you will not have to rush and can complete the job properly without needing to refill in most cases.

A single press of the power button switches the unit on and instantly water is pushed out the tip of the handle. There is no on/off switch on the handle to control the water flow.

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There are no additional cleaning modes, like some other models.

The pressure can be set to one of five different settings on the right side of the unit, by sliding the switch.

Ranging from 10 to 100 PSI, I had not expected this unit to produce as much power as it did considering its size.

Whilst you don’t have the ten pressure settings that are common on the larger units, five is good enough for most and there is no compromise on the power at which the water is expelled.

You choose the power that is right for you. Just bear in mind, the more power, the quicker the water is used. However, to gentle and you won’t necessarily stimulate the gums.

I would suggest that most people set the pressure to around three or four.

The handle comes with a jet tip fixed into it.

Unlike many other Waterpiks where the tip is removable and replaceable, this is not.

This means that approximately every 6 months you have to replace the handle or as Waterpik call it the ‘stylus’.

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It is available in Black or White to match the color of your unit and can be purchased online from Waterpiks website.

The part code is WF-04-STYLUS-WC for the white color and WF-04-STYLUS-BC for the black.

$10 is the price for just one.

The pre-fitted classic jet tip means that this flosser is suitable for the average individual, but those wearing braces, with dental restorations and periodontal pockets will unlikely get the benefits that you would with other Waterpik flossers.

The aforementioned often require more specialist tips, which are not available for the WF-04 Sidekick model.

For those who have previously used a Waterpik, you may be away that the tip could often be rotated 360 degrees on many models.

This is no longer the case here. However, achieving the same sort of thing, the whole handle swivels independently of the hose to which it is attached.

Waterpik WF-04 Sidekick review 14

So essentially you can swivel the handle 360 degrees in hand instead of rotating the tip. Similar, just different.

Squarer in design is the handle, with a very slight tapering towards the top and the bottom, there are no control buttons on the handle to stop and start the water flow, this is all controlled from the power button on the base unit.

The steps required to complete the flossing are outlined in the video provided earlier in this review, however, there are some things to note and be aware of that help you and improve your use.

It is not essential but recommended to use lukewarm water. This is because it is more pleasant on your gums when flossing.

You can use mouthwash but it would be expensive and wasteful. If you want to add an extra shot of freshness or flavor to the flossing add a capful or two to the water tank.

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Direct the jet at a 90 degree angle, working along the gumline with a brief pause between teeth.

The idea is that you spend 1 minute flossing, 30 seconds on the lower arch of teeth and 30 seconds on the upper arch.

There is no timer or pacer built into the WF-04 like there is on some other models.

Now make no mistakes if you are new to this, it is more messy than regular flossing and it will take some getting used to. Don’t be surprised by a lot of dribbling and maybe a bit of spray (it’s only water). But soon it will be easier and more enjoyable.

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Many people suffer with red, swollen or bleeding gums, which is often a sign of gum disease and that is believe it or not as a result of not cleaning correctly. It is the bacteria buildup that causes the gums to react.

Regular use will lead to healthier gums as the bacteria is removed and the gums begin to recover.

Countless studies have been completed to verify cleaning that Waterpik can provide and with 99.9% of plaque removed from treated areas, it is probably no surprise that it has been awarded the American Dental Associations (ADA) seal of acceptance.

How often you use this is up to you. Once a day is the minimum you should use it really, but twice a day would be ideal to help with any red gums you may have.

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When running, the unit is pretty quiet too.

If you have used models that are more than 3 years old you will notice how much quieter this is.

There is definitely an audible ‘pumping’ sound that comes from it, but it is not too loud and similar volume to an Oral-B electric toothbrush. It is not quite as quiet as a Sonicare brush.

In my opinion, everything about the WF-04 has been geared towards one user. Often sharing flosser with another person, be that a husband, wife, partner or the kids will allow you to get more value from it. Although possible, it is not the best product to achieve this.

A cracking product, that I would happily use on the daily, particularly when I know it is backed by a 3 year warranty.

Summary of design, usability, clean & general use

Smart and compact looking unit
Available in just 3 colors
Base unit fits inside the reservoir
Power adapter fits into the base unit
Travel case provided
13oz (400ml) reservoir
1 jet tip only
5 adjustable pressure settings
American Dental Association approved

Price & where to buy

As the market leader, Waterpik have always commanded a premium for their water flossers in comparison to the lesser known brands/manufacturers that exist.

Whilst the competition may offer better value, with Waterpik you can generally be assured of the quality, reliability and the performance.

Few other companies that I know of, actively conduct so many clinical studies to verify the performance and efficiency of their products.

Even by the pricier expectations I had, the Sidekick is most certainly a premium product, with a suggested retail price of $139.99.

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My favorite countertop water flosser is the Waterpik Aquarius has a retail price of $90 but sells for around $70.

The Sidekick commands a premium of $50, which I think is on the high side.

Yes, no doubt it has required quite some investment to make the Sidekick what it is, but I think Waterpik are being a bit greedy here. There is absolutely no denying here that you pay a premium for the form factor.

It can certainly be argued that what price can you put on your dental health…

Thankfully, online retailers, in particular, are very good at ensuring prices remain competitive, so if you head to places like Amazon to buy the Waterpik you should save at least $30-35.

I still think $105-110 is quite expensive, but $30-35 off the cost is a fair saving.

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A product like a water flosser tends to last many years, so the cost is not all that bad when you think about it.

To give you an idea of costs though, we like to price a product over 3 years here at Electric Teeth, to give a basic benchmark for comparison.

Aside from the initial purchase price, you do need to factor in the cost of replacement handles/tips, which ideally need replacing every 6 months.

The water flosser stylus for the Sidekick costs $10.

So, assuming you can pick the WF-04 Sidekick up for around $110 you then have a further cost of $50 for replacement stylus over a 3 year period, making the total ownership cost $160 or $0.16 per day.

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For the sake of comparison, the not so portable Aquarius model comes in at 8 cents per day whilst the cordless WP-560 is 9 cents per day.

Ultimately, whether you think it is worth this price will be personal opinion.

I don’t travel all that frequently, so I don’t think I could justify the price, but if I was staying elsewhere 1 or 2 nights a week for work for example, my thinking might be quite different.

Please note that all prices quoted are approximates and will vary based on location, supplier and time of purchase.  These figures were correct at the time of writing and should not be relied upon as hard fact, but used as a guide during your decision process.

Summary of price & where to buy

Recommended retail price of $139.99
An average selling price of approx $110
Replacement nozzles retail for $10 each
Daily cost as of approx 14 cents per day over 3 years

Reliability & long term use

My hands-on experience with Waterpik products has never really left me feeling disappointed and the WF-04 Sidekick is no exception to that rule.

Several weeks of testing and it is working as you would expect.

Waterpik WF-04 Sidekick review 21

It feels solid in hand and built to a high standard.

The unit is certainly a new design for the company, a different form factor, and I suspect configuration of electronics inside.

Only time will tell how well this survives long term use and transportation, but with a rich heritage of water flossers I am not concerned, especially when you get a 3 year (36 month) warranty.

This is longer than many other companies who typically offer just 1 year (12 months).


The Sidekick from Waterpik is an absolutely genius piece of kit, I like it a lot!

It is a balance of power and features whilst remaining portable.

Many people opt for cordless water flossers, just because they are more travel friendly than most other corded/countertop water flossers, but this breaks that mold.

The 13oz tank allows for a proper flossing session without interruption and the power range is simply superb.

The kicker is the price. It is not a cheap product and I understand why.

Whether you can justify this is personal opinion.

For those always on the go, that want the conveniences that come with a corded water flosser, the Sidekick has you covered.

Size guide

  • Water Flosser Height With Nozzle - 12.3cm / 4.8 inches
  • Width - 14.5cm / 5.7 inches
  • Depth/thickness - 9.9cm / 3.9 inches
  • Weight with nozzle (no water) - 478g / 16.8oz
  • Package weight - 1180g / 41.6oz


  • 79dB

Country of manufacture

  • China
Author: Jon Love

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April 14, 2024

Whilst you managed to stretch out the review through redundancy, it was still useful.

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