Measure hole center distance in the same or offset planes.
Resolution: .0005″/0.01mm.
Buttons: on/off, set, inch/mm, preset (+, -).
Automatic power off, move the digital unit to turn on power.
Battery CR2032.
Data output.
Made of stainless steel.

3M 28473, Roloc D/F Cool Running Disc Pad TR, 4 in x 5/8-11 Internal, FIN, 7000144107
Insize 6315, MICROMETER MEASURING FORCE DETECTOR, 6928640351143
3M 45179, Roloc Disc Pad TR, Medium 4 in 1/4-20 Internal, 7000045281 