Interchangeable Rod Type. The extra rigid MITUTOYO Depth Micrometer is one of the basic measuring tools selected by machinists. The width of the base, .63", by far the widest available in the market, provides extra stability in-depth gaging. The entire bottom surface is micro-lapped to achieve a higher degree of accuracy. Completely satin-chrome finished. Ratchet stop for consistent and repetitive measurements. .157" DIA. interchangeable rods, with the lapped measuring end, are calibrated and tested at the factory. The rod length can be adjusted, to compensate wear on the measuring tip, with two supplied wrenches. Crisp clear graduations on the thimble. Complete with fitted carrying case.