Shelly does not have a specific list of “Euro-only” devices, but rather a design philosophy that favours the international standard. In the Shelly ecosystem, the mounting challenge South Africans experience – where a circular rear projection prevents a flush fit against a rectangular South African 4×2 box – applies primarily to Shelly’s dedicated wall-mounted control panels.
Grab the 4×2 Adapter Plate here: https://stratlec.co.za/shop/shelly-4×2-to-euro-adapter-plate/
Devices Requiring an Adapter for 4×2 Boxes
These are the units that feature the rear “Euro-style” housing and benefit from an adapter plate when installed in South Africa:
- Shelly Wall Display (Standard): This device has a recessed rear housing designed to fit into a circular European-style flush box. When placed against a flat 4×2 cover plate or directly over a 4×2 metal/plastic box, the rear housing will keep the unit from sitting flush against the wall.
- Shelly Wall Display XL: This is the most significant “offender” regarding the rear projection. Because of its larger 10.1-inch size and increased depth, the rear structure is substantial. It is engineered for European standard flush boxes, and its circular rear housing does not accommodate the narrower, rectangular footprint of a South African 4×2 box.
- Shelly Wall Display X2i: This newer control panel model also utilizes the “power base” system common to this line of Shelly displays, which carries the same rear-projection requirement for a circular mounting cavity.
Why this happens
Most Shelly “smart relays” (like the Shelly Plus or Gen3 series) are designed to fit inside the 4×2 box behind a standard light switch. However, the Wall Display series are designed to replace the switch and sit on the surface. They prioritize global compatibility with circular flush boxes, which provide a dedicated “hole” for the rear projection to sit inside, keeping the unit thin against the wall.
Your Best Path Forward
If you are planning to install multiple units, a standardized adapter plate is the most professional solution.
- The “4×2 to Euro” Adapter Plate: You can purchase these off the shelf from Stratlec here- https://stratlec.co.za/shop/shelly-wall-display-xl/ – or have these laser-cut from 3mm acrylic or ABS. The plate should be rectangular (to cover the 4×2 box) with two holes to screw into the 4×2 box, and a central circular opening (approx. 60–65mm) to allow the Shelly rear projection to sink into the wall.
- The “Spacer/Pattress” Frame: If you do not want to sink the projection into the wall, you can use a 3D-printed “spacer frame.” This acts as a thick bezel that pushes the Shelly display away from the wall by about 10–15mm, creating enough space for the rear projection to sit inside the spacer frame rather than against the wall.
Pro Tip: Stratlec uses PETG or ABS filament. These materials handle the slight heat output from the display’s integrated relay much better than standard PLA, preventing the adapter from warping or sagging over time.