A series of Black Granite Base Comparators designed to meet the requirements of both the large and small shop. These granite bases are Laboratory Grade (Grade AA, .00005"), offer a smooth surface, are nonabrasive and extremely hard for an accurate reference plane for work inspection. All granite bases come with a Certificate of Accuracy, traceable to N.I.S.T..
These 6" x 6" x 2" granite bases are supplied with a 1.25" diameter, 8" tall column and an indicator arm (rigid or with a fine adjustment knob).Indicator arms are available in lug or stem mount. Indicator arms have a throat depth of 1.75" and can be raised to a height of 6" depending on the type of mount used.
