What does MR3 mean?

Looking for the full meaning of MR3? From the following image, you can find out all definitions of MR3. If you want, you can also download image file to print.

What does mr3 stand for

MR3Machinery Repairman Third Class
MR3Maintenance Release Number 3
MR3Mercury-Redstone 3
MR3Military Region 3
MR3Mode Register 3