Fowler 53-670-002-0, Micrometer Calibration Set with Steel Blocks and Optical Flats

Includes NIST Certificate 11 Pc. 9 rectangular gage blocks and two optical flats. Fitted wooden case Features Grade Assists in meeting both Federal specification GGG-C-105c and ISO 9000 requirements. Contains one block of each of the following sizes: .0625, .100, .125, .200, .250, .300, .500, 1.000 & 2.000" TWO OPTICAL FLATS that vary in size by .0125" which allows checking anvil faces at half revolutions of spindle for measuring flatness.