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Well that's a quite simple question. I tried my chance with Google Images without success and tried some lists of images to be able to know what is this component. But I don't find it and there is nothing written on it.

enter image description here

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up vote 27 down vote accepted

This is Light dependent resistor (LDR).

Its similar to a normal resistor, but the resistance decreases with increasing light intensity.

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Perfect! Thank you O.Blue I can put a sticker on it now :) – rels Feb 20 at 14:19
If the answer seems good to you, don't forget to accept it (button just below the up/down vote arrows). It allows to mark the question as answered – MaximGi Feb 20 at 14:37
Possibly worth mentioning that these are generally based on Cadmium Sulfide (CdS), and are therefore not RoHS-compliant (Cadmium is on the no-no list). Use ambient light sensor (the generic term) for plenty of RoHS-compliant options. – Calrion Feb 21 at 5:57
Do they only work for visible light or can you get ones for ultraviolet, infrared, etc light as well? – Pikamander2 Feb 21 at 6:31
@MiximG wanted to do it straightly but had to wait "10 minutes" and had to go, so it's done only now. – rels Feb 22 at 7:43

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