What is this sensor? I'm confused and don't know what it is for. Possibly motion? Please advise.
Need a clearer, closer view. It looks like a 32kHz crystal to me.
Yup - it looks like it's almost certainly a crystal; I can't tell what the markings on it are, but if you post them, we'll tell you for sure.
It could also be a spring-based motion sensor, but those are usually shorter and wider diameter.
My guess is a motion sensor switch.
Could be tilt sensor, used a DVM, see in there is continuity between leads when turned.
May be a crystal.
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Looks like a tilt sensor ( case looks to be copper/brass colored, not usually seen on an xtal).
123Splat:
Looks like a tilt sensor ( case looks to be copper/brass colored, not usually seen on an xtal).
I think that color's a reflection, not the actual metal color.
I took a glance at some tilt switches on Mouser and even the cylindrical ones don't quite look like that. On the other hand, it is exactly the right proportions for a 32.768 kHz watch crystal, so that's what I'm laying my money on.