I'm working with the DYP-ME007Y ultrasonic sensor for a project and I bought two off eBay. Both seem to work however they have this 'unknown' twistable part which is in a different position of rotation on both. I have a suspicion it is a trim pot of some description, but I would like to make sure. It could possibly be a method of tuning.
The part in question is the tall silver component with the black circle on top. The only writing on it is 7708, on the other side.