Ok, I was cleaning out a 'junk' drawer and I came across this device in a zip-lock bag. I know I kept it for some reason, but for the life of me I can't remember why or where it came from or what it is, Doh!
It measures about an inch long and 1/4 inch square. The electronics are entirely sealed in some sort of acrylic and there are two leads on the bottom. Two watch batteries are visible. The top has a hole and within the hole is a small metal shaft (see pics). If I had to guess, I'd say the device acts as a small solenoid that can lower the shaft for something to pass through the hole. Or maybe the shaft is used to lock something in place.
I know this has nothing to do with the byoac hobby, but I'm thinking one of us might have an idea what this thing is for - before I toss it out and regret it later!