What are these clip-like things? With me becoming an aviation enthusiast and AirBerlin becoming insolvent, my mom has gone on a hunt for deals on what I can best describe as AirBerlin merch (old uniforms, shirts, skirts, belts and many more).

In one of the packets that arrived recently she found items that neither her nor I knew the purpose of.

They are about 2cm * 2cm, yellow, have some kind of number on them and on most of them was the writing "Air-Berlin SEALED" or "airberlin group SEALED" and an engraved "PULL". It also looks like you can break off and bend a part in the plastic to the back and clip it there.

Below is a picture I took of a few of these:
Galley seal. It works like a cable tie, you can put one end inside a hole on the main body but you can't pull it out without destroying the seal.

The cabin crew will seal the galley carts containing alcohol and other duty-free items before landing and note the seal numbers in their report. This is required by law in a lot of countries.