The ring that seats the main switch neatly in the panel
The main switch of a Rocket sits in the housing panel from behind and is screwed in place from the front with a decorative nut. It has two jobs: it holds the switch firmly in place, and it gives the opening a clean, chrome-plated edge instead of a raw hole in the sheet metal. The part number is A529904989.
It usually gets lost during a repair – it is small, it rolls, and it never turns up again. But it is also replaced when the chrome plating has become stained, when the thread was stripped by overtightening last time, or when the switch can no longer be tightened and wobbles in the panel. A wobbling switch is not just a cosmetic flaw: every time it is pressed, it puts strain on the connections behind it.
When it's due
- The main switch wobbles in the panel or can be pushed in.
- The decorative nut was lost during servicing.
- The chrome plating is stained, tarnished or chipped.
- The thread no longer grips properly or has been stripped by overtightening.
- The front panel is being replaced and the trim parts are to be replaced with it.
At a glance
| Type |
Decorative nut, purely mechanical |
| Installation location |
On the outside of the housing panel, at the main switch opening |
| Fits |
Rocket espresso machines – the documentation does not name a specific series |
| Scope of delivery |
One decorative nut. The main switch itself is not included. |
| Part number |
A529904989 |
| Version |
Thread size and diameter are not documented |
| Installation |
Installation by a qualified technician recommended |
| Brand |
Rocket Espresso |
Who it's for
For anyone who has lost the nut or whose main switch has play in the panel. The part costs little and makes the most visible spot on the front tidy again.
Important for installation
Even though the nut itself is not an electrical part, it sits directly on the main switch, and behind it is mains voltage. Before any work, the machine must be switched off and disconnected from the mains, and the power plug must be pulled out, not just the switch turned off. We deliberately do not provide step-by-step instructions here – work near mains voltage belongs in expert hands.
What goes with it
From our workshop in Bern and Zürich
When disassembling, we always put small trim parts in a magnetic tray and never on the workbench. A decorative nut that has once rolled under the cabinet costs more time than all the rest of the panel. That is our routine, not a manufacturer requirement. Once the machine is running again, there is an espresso for the final check – ideally Nutty Delight or Cozy Chocolate, or, for something stronger, Very Nutty. More under Coffee beans.
Returns excluded
Original spare parts are excluded from exchange and return. They are procured specifically for your order and cannot be resold after being installed or test-fitted on the machine. So before ordering, check the model, year of manufacture and serial number of your machine – or send us a quick message and we will clarify the fit together. Your rights in the case of defective goods remain unaffected.
Frequently asked questions
Is the main switch included?
No. Only the decorative nut A529904989 is supplied. We do not offer the switch itself in the shop – we do not sell electrical components online.
Is the decorative nut an electrical part?
No. It is a purely mechanical trim part made of metal. However, it sits directly on the main switch, behind which there is mains voltage – hence the installation note.
What thread size does it have?
This is not stated in the documentation. Measure the old nut or send us a photo with a scale, and we will check before you order.
Which series is it for?
The documentation does not name a specific series. Send us the model and serial number of your machine, and we will check the fit.
Can I see the part at your showroom?
Yes, of course. You'll find us in Bern at Gerberngasse 44 and in Zürich at Hagenholzstrasse 50b.
Questions about fit? Write to us at [email protected]. We deliver across Switzerland and to Liechtenstein in 2-4 working days.
