The sale of all lighting equipment for bicycles on the Amazon.de website must be in compliance with the requirements of the German Road Traffic Ordinance (Strassenverkehrszulassungsordnung - StVZO). According to the StVZO, bicycle lights and other lighting equipment for bicycles can only be distributed in Germany if the manufacturer has been granted a general type approval (Bauartgenehmigung) for the product by the German Federal Road Traffic Authority (Kraftfahrtbundesamt). The general type approval is documented by an approval mark and approval number that must be affixed on the bicycle light itself. Please note that bicycle lights with a blinking setting are generally not permitted in Germany and will hence never have a general type approval. The approval mark is always a sine wave followed by the letter “K” and a 4-digit number:K****
Please note that lighting equipment that falls under this regulation is every equipment that is objectively capable to be affixed to a bike. For example, it is irrelevant if the product is designated in the advertising claims to be for a children scooter, hiking stick or backpack, or if the advertising contains a disclaimer that the product is intended for offroad use only and not for road traffic – if the product is objectively capable to be affixed to a bike then the product must have a type approval as outlined above.
Additional information can be found here:
Example of Bicycle Light Approval Mark: