Starrett 128BZ Vernier Inside Micrometers Set, 6-150" Range, 0.001" Graduation, +/-0.0001" Accuracy

The set consists of a satin-chrome micrometer head which can be used in combination with any one or more of a series of rigid, tubular steel measuring rods to obtain the required length. The micrometer head is a modification of our No. 63, which has a 2" range. The head has a basic length of 4" which can be lengthened to 6" by means of its measuring range. Interchangeable tubular steel measuring rods and extension rods are lightweight with extreme rigidity, rods screw into each other and seat against hardened ground and lapped surfaces necessary for high accuracy, rod diameter 5/8". Movement of screw: 2", Range with Combination Head: 11-155". Set includes (1) 4-6" Head, (1) each 2", 4", 6", 8", 10", 12" Rods, (1) 12" extension rod, (2) 24" extension rod.