When you go to Premium-PC-Steckernetzteil ("Rydges® High-Quality PC Netzteil - by OTB 2A - / 2000 mAh Ladegerät 5V 2000 mAh für Raspberry Pi Modell A und B & Banana Pi - Pi Model B+ (B Plus)" - I'm sorry, it's the German amazon website) you can see from the title it is about a power supply unit for raspberry pi. However, when you scroll down to the ratings / reviews it is clear that they are about cases for raspberry pi.
See the link for an image of the page. It is quite large, so I don't want to include it here directly.
Why did Amazon mess that up? Is it a bug?