Which tool

[Brockett]

Previous DIY mechanic has inserted valve shims upside down. Those shims have their size numbers worn off and other shims have uneven surface wear. OK so now I have to measure these shims in order to obtain their size and buy replacements.
I do not have an accurate device and wonder if I go for a micrometer or a verier type guage. Also can anyone recommend a make and possible supplier.
Note I have a cheapo digital vernier type guage and the jaws are not parallel and it gives a false reading that is too inaccurate for measuring shims.

[Rixington43]

I have a set of digital verniers that I believe came from Aldi or Lidl, they seem perfectly accurate as measured by a micrometer as well. I find verniers more useful as a general tool to own around the house if that features in your decision.

[crump]

Vernier calipers more useful in general  but personally I'd prefer the accuracy of a micrometer for valve shims. Luckily I have a couple of good micrometers which I liberated when made redundant from Dunlop engineering in 1980.

[nigel s]

I have these ,
https://www.ebay.co.uk/itm/315045533668
They are pretty good and give repeatable readings I.e. when you measure something twice it gives the same reading.
Though the engineers Micrometers at work are better.
Depends how much you want to spend.

[purplebikeunicorn]

I have a set of Silverline calipers (Amazon), use them for all 3D printing stuff and other tasks.

If your current calipers are repeatable, but just not accurate, can you measure the shims you know the size of, and adjust the other readings?

[Robotstar5]

Look for a micrometer on ebay etc. plenty of quality makes such as Moore & Wright, Starrett and Mitutoyo for a few quid, all the better if you get one with it's gauge block as you can verify it's accuracy before use.