No More Guessing
I bought a Toolzone 150mm Electronic Digital Vernier Caliper from Amazon, to measure skate wheel sizes.
As skate wheels wear, its sometimes hard to guess which size fits.
I tend to check my skates, after every usage. I check frame for damage, and wheels for wear and rotation.
Before I bought the caliper, I would eye it up and guess the sizes, also taking into consideration the sometimes uneven wear. Using the caliper, I've accurately graded and sized all wheels ready for usage.
Its a nice tool with a digital readout, so no more guessing. At £10, its not expensive.
It can take internal, external and depth measurements, and comes supplied with a hard plastic case for protection.