What is this 12mm long 2mm dia glass tube with a coil inside? SOLVED It's a transponder

[waigy]

I found this on the floor and I'm concerned it might have fell off something I need.
Anyone know what it is?
It has a tiny coil inside wrapped around a black cylinder.
The glass is perfectly round and shiny on the ends and I can't see any external solder connections or bare wires anywhere when looking with a magnifying glass.
It looks like the coil is fully enclosed in glass.

Things it could possibly be from are :
I'm working on my motorbike, but it's a 1985 motocrosser so no computers or high tech electronics.
My soldering iron has overheated once.
One of my multimeter probes came away from its cable.
Could be from a 1989 pocket TV.
A Chines digital speedo for the bike (I took it apart and looked at the circuit board and it doesn't look like it is missing from there).

 

[Geoff1946]

I think it may have fallen out of one of your car keys. It looks like a transponder chip

 

[waigy]

You're right. Googling "transponder chip" finds the exact same thing.
It's not from my own car as my key works fine.
Cheers

 

[Andy™]

its what the government has put inside you to track you. dont let them know youve 'lost' it