The Mitutoyo 137-205 Extension Rod Tubular Inside Micrometer – Metric has the following specifications:

? Range: 50 – 1500mm
? Travel of micrometer head: 13mm
? Accuracy: +/-(3+n+L/50)?m L=Maximum measuring length (mm) n=Number of rods Fraction rounded up
? Graduation: 0.01mm or .001″
? Extension rods: 13mm, 25mm, 50mm (2 pcs.), 100mm, 200mm (3pcs.), and 300mm (2 pcs.)

Features:
? Wide range of ID measurements by combining extension rods (pipes) and anvils with the micrometer head.
? Carbide-tipped measuring faces are available.
? Supplied in fitted plastic case except 1500mm / 60″ come in wooden case.