Review on Rectangular Grade Certificate 303 5308C by SHARS by Brian Garrett

The case for my set was damaged in transit but Shars/Discount Machine Shop sent me a new case as soon as I contacted them about it. I'm sure I'll be shopping with Shars again - and probably sooner rather than later! All I can say about the accuracy/accuracy of gage blocks is that I would need an air-conditioned lab clean room full of very expensive equipment to test them. LOL, even the smallest of those "economy class" gauge blocks are only a few millionths of the advertised thickness. According to the tolerance chart included with the kit, they average less than 20 millionths of an inch of the specified thickness—50 times more accurate than my next best gauge, the Mitotuyo 0.0001-inch dial indicator. I plan to use these blocks for the rest of my life testing every other tool in my home business. Barring accident or negligence, they will be just as good for a future owner in a hundred years.