I received the latest set from Revain at a retail price of $69. A good buy at this price. At the listed factory price, Revain's 81 piece set is a much better buy as of April 11, 2018. I wanted it to check the accuracy of a caliper and micrometer and in my opinion it's perfectly fine for that kind of use. The 81-piece set is best suited for flat panel work, such as B. the installation of height gauges or the determination of the cutter height of a milling machine, as well as for other applications in machine shops.