Fowler Full Warranty Inch Digit Outside Micrometer, 52-224-002-0, 1-2" Measuring Range, 0.0001" Graduation Outside micrometer with choice of measuring range, and flat anvil/spindle pair with 0.256" diameter measuring face for general purpose measuring Digit display has 0.001" graduations and Vernier scale to 0.0001" and an accuracy of 0.00016" (0-1" model) for precise readings Hardened and precision-ground anvil and spindle have micro-lapped carbide measuring faces with 0.00008" parallelism on 0 to 1" micrometers and 0.00003" flatness for accurate measurements Hardened, ground and lapped spindle thread provides smooth movement, accuracy, and long life Ratchet stop applies constant force for repeatability between users