Dasqua 2-20" 0.001" Inside tube micrometer resolution is 0.001". extension rods included are 0.5", 1", 2" (2pcs), 4", and 8". Accuracy is 0.00065". Strictly made in accordance with DIN863. Hard chrome plated. No-glare satin finish. Included extension rods provide a wide measuring range. Supplied with a standard gage for zero setting. Measuring rods hardened, ground and lapped. Includes one standard micrometer head from 50-63mm and various extensions. One or more extensions can be screwed into the standard micrometer head depending on the desired measuring range.