These made-in-America micrometers have been around since before any of us can remember and they're still a very good all-purpose micrometer. If your union requires you to use tools made in the U.S.A. then this is an obvious choice.
The anvils are carbide tipped and the .0001" straight line graduations on the thimble are quite easy to read compared to other brands. It's certainly the best of the American made micrometers, yet at a value price.
We're promoting the complete sets as well as individual micrometers. These meet Federal specifications but do not come certified. Standards (calibration measuring rods) are not included with individual micrometers but could be bought separately. These complete sets come in a wooden storage case and optional setting standards.
Set 599-181-923 has three micrometers, but the wooden box leaves room for a fourth, should you choose to add one at a later time. The spanner wrenches (included) are used for zero-setting of your micrometers. If you've lost the wrenches, you can order replacements below.
Because of their low price, these micrometers are usually not economically repairable. You can easily replace individual micrometers in a set, if necessary.
Reference: BS-10 2016 edition