The new Samsung Galaxy Z Fold3 was just announced, debuting as the first folding phone with stylus support for the brand-new S Pen Fold Edition. With this re-imagined S Pen, one of the questions I’ve been asked a lot is whether the Fold Edition will work on non-foldable devices. Well, it sort of does.

The new model is a little different than S Pens of years past. Samsung had to design a new internal mechanism for the S Pen Fold Edition so as not to damage the delicate foldable panel when writing on it: A spring in the body makes it impossible to put too much pressure on the display without the tip retracting. While the underlying technology from Wacom is the same, the phone does read these styluses differently, so the Z Fold3 knows not to let you use a non-Fold Edition pen.

Due to the differences with how the phones communicate with the stylus, previous Note-series devices and the S21 Ultra will see this new S Pen’s tip as… an eraser? You can still use it to control the device, but if you try to write with it, all it will do is erase. That’s more than the Note 20 Ultra can manage, though, which doesn’t seem to recognize the new S Pen at all — unless you basically smash the pen into the display until the tip is fully retracted.

If you’re looking for a S Pen that will work on both your new Z Fold3 and previous Note devices, Samsung does sell the S Pen Pro — this one has a switch that lets you choose between classic S Pen mode or compatibility with the Z Fold3. It also has Bluetooth smart features to control your device and supports the Tab series of Samsung slates.