Starrett 824A Fixed Range Vernier Inside Micrometre, 3-4" Range, 0.001" Graduation, +/-0.0001" Accuracy

The Starrett 824 series fixed range Vernier inside micrometre has an adjustable sleeve and adjustable contacts on the thimble end help provide accurate measurements, and a Vernier scale in inch units for making precise measurements. A knurled thimble helps provide secure grip, and the handles are heat-insulated to help reduce temperature-related expansion or contraction. The Vernier scale is graduated to 0.001” and a knurled ring-type lock nut holds measurements in place. The micrometre has a satin chrome rust- and glare-resistant finish. Micrometres are precision measuring instruments that use a calibrated screw to measure small distances. These measurements are translated into large rotations of the screw that are then able to be read from a scale or a dial. Micrometres are typically used in manufacturing, machining, and mechanical engineering. There are three types of micrometre: outside, inside, and depth. Outside micrometres may also be called micrometre callipers, and are used to measure the length, width, or outside diameter of an object. Inside micrometres are typically used to measure interior diameter, as in a hole. Depth micrometres measure the height, or depth, of any shape that has a step, groove, or slot. The L.S. Starrett Company manufactures precision measuring tools, metrology and testing equipment, and saw blade products. The company was founded in 1880 and is headquartered in Athol, MA.