Test result preview
Manufacturer’s product description
The moinkerin 17 mm wheel bolt caps (set of 20, black) underwent practical testing in our review. The product is aimed at end consumers who want to enhance the appearance of their wheel nuts and bolts while also protecting them reliably against corrosion and dirt. The manufacturer promises high-quality plastic, easy installation by simply snapping them on, and an installation tool for removal.
In our test, the set impressed with its stable fit, neat finish, and subtle, glossy black appearance, which blends inconspicuously into different rim designs. Its universal compatibility with 17 mmhex wheel bolts and the option of concealing old nuts are advantageous features – a quick rim refresh without the need for a workshop.
On the negative side, we noticed that there was no information about the sustainability of the materials and that some of the caps had minimal micro-scratches from the factory. In addition, the packaging is made entirely of hard plastic, which could have been avoided.
Overall, the set offers solid screw protection at a low price and is interesting for users who are looking for car accessories that are easy to use but do not expect a premium feel.
Advantages
- Quick and easy installation
- Uncomplicated corrosion protection for nuts
- Unobtrusive design, glossy black
Disadvantages
- Hard plastic packaging
- Occasional micro-scratches
First impression
Packaging and contents
Here, we take a closer look at the packaging. Sustainability is becoming an increasingly important factor. In addition, adequate protection of the product must of course be guaranteed. Is the packaging complete and does the manufacturer make it as easy as possible for me to use the product straight away?
Here, the packaging is examined in more detail. Sustainability is becoming an increasingly important factor. In addition, adequate protection of the product must of course be ensured. Is the packaging complete and does the manufacturer make it as easy as possible for me to use the product straight away?
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Comment
Score achieved*
Product protection
Packaging is sturdy, product adequately protected
Points
Sustainability of packaging
No unnecessary packaging waste, but unfortunately plastic is used
Points
Package contents & scope
Complete
Points
Instructions
Illustrated instructions in German and English.
Points
TOTAL
95
Points
Weighting: 20%
*The maximum number of points is 100
The 17-millimeter wheel bolt caps arrived neatly packaged and perfectly fitted; the outer packaging is tailored to the product size, eliminating empty space. Positive: The product is well protected – all parts arrived undamaged and without significant soiling, and the surfaces of the plastic caps are mostly smooth and shiny ex works. We are critical of the sustainability. The packaging is made entirely of hard plastic. Cardboard or mixed cardboard would be perfectly adequate and more resource-friendly for such a robust car accessory. The package contains everything you need: 20 wheel bolt caps and a small installation tool (pull-off clip), making the set suitable for a complete set of wheels including a spare. Strictly speaking, instructions are not necessary as the product is self-explanatory. However, illustrated instructions in German and English are included, which are helpful for first-time users. Overall, the initial impression is one of functionality: screw protection, corrosion protection, and visual enhancement are clearly the main focus. There is room for improvement, particularly in terms of packaging ecology.

First impressions
Product workmanship and appearance
Before we put the products to the practical test, we take a close look at their workmanship. How high-quality are the materials used? Are the feel and appearance satisfactory?
Before putting them to the practical test, we take a close look at the workmanship of the products. How high-quality are the materials used? Are the feel and appearance satisfactory?
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Comment
Score
Visual appearance
Appealing design
Points
Workmanship
Good workmanship, minimal scratches on the top, no functional limitations
Points
Stability
Very stable for its intended use
Points
Sustainability
No information, multiple use possible
Points
OVERALL
88
Points
Weighting: 20%
*The maximum number of points is 100

In hands-on testing, the moinkerin wheel bolt caps appear to be cleanly manufactured overall. The edges are free of burrs, the fits are even, and the high-quality plastic gives a durable impression. The visual appearance is deliberately unobtrusive: the glossy black finish (in the test) blends neutrally with various rim designs and wheel hubs. Alternatively, there are versions in silver and sizes of 17 millimeters and 19 millimeters for different wrench sizes. In direct light, some caps showed slight micro-scratches or minimal matt areas – presumably due to transport or packaging. This does not impair the functionality of the caps, but detracts from the perfection of the finish. In terms of stability, the caps make a very good first impression. The overall impression is one of high quality and robustness. The pull-off clip seems a little flexible, but this is appropriate for the intended use.
From a sustainability perspective, further information on the origin of the materials or the recycled content is lacking. Nevertheless, the durability of the material ensures a certain degree of sustainability over its service life, especially as the caps are reusable across models and help to prevent premature replacement of corroded nuts by protecting the screws. All in all, the workmanship delivers what consumers expect in the wheel nut cap segment: solid manufacturing quality, practical robustness, and a discreet appearance without conspicuous branding.
This is what our practical test revealed
Does the manufacturer deliver on its advertising promises?
Our practical test is the most relevant and therefore carries the highest weighting. Here, the product has to undergo a wide range of criteria and tests. We check the functions and product promises of the test item.
Our practical test is the most relevant and therefore carries the highest weighting. Here, the product is subjected to a wide range of criteria and tests. We check the functions and product promises of the test item.
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Comment
Score achieved*
Assembly
Easy to insert and remove using pliers, self-explanatory
Points
Stability
No deformation or breakage detected
Points
Scratch
Protection against scratches on materials commonly used in applications
Points
Compatibility
Available in 17 and 19 millimeters, for most European manufacturers
Points
Cleaning
Easy to clean with standard household cleaners
Points
OVERALL
100
Points
Weighting: 45%
*The maximum number of points is 100
Our practical test largely confirmed the manufacturer’s specifications. This includes, first and foremost, ease of use: the caps are simply pressed onto the wheel bolts and sit securely in place immediately. To remove them, the clip supplied is hooked into the groove and pulled off again without any effort. This push/pull process is self-explanatory and can even be done with gloves on. No limitations were found even after repeated (dis)assembly.
In terms of stability and durability, we did not notice any deformation or breakage during normal use; the plastic is sufficiently tough and temperature-resistant for normal car use.
The surface is scratch-resistant enough for everyday use: contact with soft to medium-hard materials (such as the rough side of a household sponge) leaves no noticeable marks. Hard rubbing with stone or steel can cause visible scratches, but the cap still fulfills its purpose as a sacrificial layer that protects the nut from corrosion and visual damage.
Compatibility is as specified by the manufacturer: This set fits 17 mmhex wheel nuts. The manufacturer also offers 19 mm versions. This covers the wrench sizes commonly used in Europe for typical M14 wheel bolts. Non-European, especially Asian manufacturers often use different combinations, so the wrench size should be checked before purchase.
Cleaning is straightforward: the caps can be cleaned with standard household cleaners or as part of a car wash; no additional care products are required. Overall, the core promises – easy installation, screw protection, and visual enhancement – are kept. Critical points remain the hard plastic packaging and the lack of sustainability information. For end consumers who want to achieve a clean look and solid corrosion protection on a low budget, the moinkerin wheel bolt caps are an inexpensive and functional choice.

Test plan
A detailed insight into the evaluation criteria for the practical part of the test and the points awarded can be found here. If you are also interested in the evaluation of our other test criteria, please read our document on the evaluation process.
Price/performance
and consumer reviews
Finally, we examine how the product compares to the competition. Can it compete with the competition in terms of price and quality? Would we generally recommend it for purchase?
Finally, we examine how the product compares to the competition. Can it compete with the competition in terms of price and quality? Would we generally recommend it for purchase?
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Comment
Score achieved*
Price/performance
Very good performance in the mid-price segment
Points
OVERALL
80
Points
Weighting: 15%
*The maximum score is 100 points
Prices of up to $12.99 are charged online for equivalent products. Very inexpensive products are available starting at $4.99 . The wheel bolt cap set from moinkerin is therefore currently in the mid-price range at $7.99. The price-performance ratio is very good for the quality and performance received.
Overall
Weight
Score achieved*
1. Packaging & contents
2
Points
2. Product processing & appearance
20
Points
3. Practical test
45
Points
4. Price/performance & consumer reviews
15
Points
TOTAL
Points
*The maximum score is 100 points