Shars Grade Economy 81 PCS Rectangular Gage Block Set with NIST traceable certificate 303-5311C M}

I read about Jo-blocks in Simon Winchester's recent book, "The Perfectionists." He writes about them in the prologue. I just had to have them. I think mostly I purchased them because 15-20 years ago a set not as good as these would cost north of a few thousand dollars and maybe more. Today - they cost less than $100, all because of the things outlined in Winchester's book.However, the embarrassing thing is, other than ensuring my digital calipers are spot on, I can think of no other uses for these as yet. I'm not a machinist and don't have tools (other than my digital calipers), that need anywhere near this level of calibration. But they are just so wonderful and perfect, I can't help taking them out and just looking at them. If you know of any other good uses for them, I'd love to hear about it.

All of that can be overlooked since I can clean them and oil them properly, but the one thing that I wish I had realized before purchasing these was the fact not all of them were the same dimension when stacking/wringing. If you are trying to measure an accurate cutout hole or slot on something, if you are using a thinner block in your stack it will get pushed. If all the blocks had the same dimension on the mirrored side, I would be extremely grateful. I took a chance on a company I wasn't too familiar with and for its price, I'm willing to take some issues. I hope they have an updated set that will have the same dimension going forward. precision 1-2-3 blocks are next!

Nice

Good for what I need them for, usually just in a sine vise/chuck.

Starting with the box; it is well made and does not cause aggravation. The outside is a durable laminated wood. Inside where the gauge blocks rest is a hard plastic tray that will outlast a wooden one that some sets come in. Each block is clearly and neatly separated by size. The blocks came with an oil paper resting over the top rather than each one being individually wrapped, so they are ready to use. Included is an NIST test report. The blocks fall within grade, so you are certainly getting what you pay for.