Wheel bolt and nut caps – what they do and how to choose the size
Caps cover the heads of wheel bolts and nuts. They improve the look of the wheel and protect the heads from road salt, water and dirt – fitting takes a few minutes.
Updated: October 2026 · Author: KLUCWERK / Akcesorex team
Key points
- Cap size = the wrench size you use for your wheels (17 or 19 mm).
- They fit both bolts and nuts.
- They go on without tools and come off with the supplied removal tool.
What caps do compared with bare bolts
- They shield the heads from water and moisture, winter road salt, mud and brake dust.
- Less rust on the heads – bolts stay clean and easy to undo after winter.
- A uniform wheel finish – chrome or black.
- Fitted without removing the wheel, without tools or a workshop.
How to choose the size
Check the wrench size for your wheels. 17 mm is standard on e.g. the VW Group, BMW and Mercedes. 19 mm – e.g. Ford, Opel/Vauxhall, Renault, Toyota and Korean cars. If unsure, measure the bolt head across the flats with a caliper.
KLUCWERK caps – specifications
| Sizes | 17 mm and 19 mm |
|---|---|
| Colours | chrome, black |
| Material | UV- and frost-resistant ABS – does not fade in the sun or crack in frost |
| Set | 20 pcs + removal tool |
| Use | alloy and steel wheels (with wheel covers open at the bolts) |
| Warranty | 24 months |
What to check before buying
- UV- and frost-resistant material – caps sit outside all year round.
- Removal tool included – makes taking the caps off easy at wheel changes.
- Quantity – a full set of wheels usually needs 16–20 caps.
- Exact wrench size – a 17 mm cap does not fit a 19 mm head and vice versa.
Questions and answers
Do the caps fit wheel nuts too?
Yes – they fit both bolts and nuts tightened with the same wrench size.
Do I need to remove the caps before changing a wheel?
Yes, remove them with the supplied tool before undoing the wheel and refit them after tightening.
Source and fitment
This guide is based on the Akcesorex knowledge base – original article (in Polish) on akcesorex.pl. KLUCWERK parts can be matched by make, model or VIN in the Akcesorex fitment configurator.