Wow! This is a special order micrometer that reads in .0001"
It is a variation on the blade micrometer.
The advantage of the blade micrometer is that it does not screw into the work ....
it moves straight down to contact the work.
Starrett does amazing work!
This duck has a chemical reaction ...... shake it up and it has flashy lights inside .... but they don't show up on the camera ..... it might be sort of a vampire duck (vampires don't show up in a mirror)