Mitutoyo Screw Thread Micrometer 0 25mm x 0.01mm Screw Thread Micrometer ISL4 01mm graduations Inside Micrometer set 01mm graduations Inside Micrometer set Tubular Extension Rod style A wide range of inside measurements is possible by combining extension rods and anvils with the micrometer head 6 extension rods included SJ or SH are specified Best possible repeatability is achieved from Mitutoyo Micrometers 01mm graduations Screw Thread Outside Micometer Anvils and spindle tips are interchangeable in matching pairs to enable measurement of Metric Unified or Whitworth threads Direct reading of screw pitch diameter (no need for calculation) Equipped with ratchet stop for constant measuring force Interchangeable anvils are optional and are ordered separately