78/782F Extensions for 781XT AccuBore Electronic Bore Gage

78, 782 Internal Micrometer Extensions
Internal Micrometer Extension, 1/4-5/16" (6-8mm), 2.5"

The Starrett Internal Extensions for 78 Series Internal Micrometer includes 1/4-5/16" (6-8mm) sizes, 2.5" extension size, and fits models 78XT/780XT/781XT-312-375. Extension 2.5"/63mm Long for use with 78/780/782, 312-375.

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  • Extensions can be added to both the 780XT and 78XT Series, enabling internal measurements in deep hole bores. (Multiple extensions can also be used.)
  • 2.5" Length


  • Fits Starrett Series: 78XT/780XT/781XT/782XT–312-375

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