Micrometer Depth Gage, Ratchet Thimble, 0-3" Range, .001" FEATURES The depths of holes, slots, shoulders and projections can be measured with these fine tools 2-1/2" (63.5mm) base and 1/8" (3.2mm) diameter measuring rods Combination ratchet and speeder for uniform pressure and quicker adjustment Ring-type knurled lock nut for quick and sure locking SPECIFICATIONS Made in America: Yes Micrometer Type: Mechanical Range (in): 0-3" Graduations (in): .001" Base Length (in): 2-1/2" Lock Nut Type: Ring Type Knurled Measuring Rods (qty): 3 Rod Diameter (in): 1/8" Thimble Type: Ratchet Case Type: Padded Case Accuracy (in): Mic head +/-.0001"; Rods +/-.0002"