Heh, finally perhaps i've found one difficult to guess :eg:
Plastic, not metal ..... nothing to do with brakes (also if it stop things
) ..... nothing to do with power grids (nor with any other type of energy control
) ..... nothing to do with cars ..... the round part is 24mm external diameter, and the hole in the middle is less than 1mm (this for give dimensional scale
) ..... as i've said, all you have at least one (maybe more), but 99% of you never seen it, nor know that it exist (and this is the funny part :eg
..... Also, the shape is not relevant, other models are just round, or rectangular, or squared
Too much helps ..... i'm too good, i know :eg: