No worries man. That's why we're here. I worked as a machinist, so I always had high end measuring tools. I have never used the ones I linked ya, but two of my friends have bought those after I showed them those and they love them. Plus the reviews are really good, by some machinists even.
Oh...
Let me find you a decent one on Amazon...
Digital Caliper, Qfun 6 Inch Caliper Measuring Tool Extreme Accuracy IP54 Waterproof Digital Micrometer Stainless Steel Electronic Vernier Caliper with Extra Large LCD Screen, Inch/Metric Conversion https://a.co/d/5pCJJXY
Make sure you click the coupon...
A caliper comes in very handy in the RC hobby. One of my most used tools, but I do a lot of 3d printing and part design. But they come in real handy for measuring screws and such as well.