Review on Busy Corner Telescoping National Measuring Thickness by Bim Cook

I'm replacing a couple of O-rings on some vintage gear. I was able to find the kit but wanted to write down the measurements in case kits become unavailable in the future. Size charts never seem quite right so I went with these. It works great but a lot more than I expected. I am checking size 015 to 117 but this one is much larger. It works for me, it's easy to use and accurate, but it doesn't fit in my small tool box like I planned.