From the Interpol website

https://www.europol.europa.eu/stopchildabuse

"The most innocent clues can sometimes help crack a case. The objects are all taken from the background of an image with sexually explicit material involving minors. For all images below, every other investigative avenue has already been examined. Therefore we are requesting  your assistance in identifying the origin of some of these objects. We are convinced that more eyes will lead to more leads and will ultimately help to save these children.

Can you help us recognise the objects? We specifically want to trace their origin (location/country). You can help by clicking on an object you recognise and providing Europol with the information you have on the object. This can be done anonymously. Once the origin of an object is identified, we will inform the competent law enforcement authority of the involved country to further investigate this lead and hopefully speed up the identification of both the offender and the victim"