You can find your edelkrone product's serial number on the bottom of the original product box.
In some cases, for newer generation edelkrone products, the serial number may be located on the unit itself.
For example, past generation products such as the SliderPLUS v3 and previous models (v2 - v1) do not have the serial number on the unit itself. The serial number for these units are located on the original product box.
On the SliderPLUS v4 (and later generations), it can be found on the bottom of the unit, on a silver sticker with a barcode under the number.
Here's an example below of a SliderPLUS v4: