Easy-to-read white dial is 2.2" in diameter Includes NIST traceability certification and fitted case Stem diameter is 3/8" (8mm) with #4-48 (M2.5) thread Universal positioning capability Jeweled bearing With counter pointer and internal tolerance marker For over 60 years, SPI has introduced innovative products to the metalworking and laboratory industries. SPI measuring instruments are durable, precise, and reliable — all backed by an industry-leading 2-year warranty. SPI's 22-310-7 deluxe AGD2 dial indicator has a 2" Range and 0-100 Dial Reading. 0.001" Graduations on 2.2" Diameter Dial, 0.1" Range per Revolution, 0.004" Accuracy, Revolution Counter, Includes NIST Traceability Certification.