770BXTZ-312 Electronic Internal Micrometer, 3-Point Contact 72544

770BXT Electronic Digital Internal Micrometers
Electronic Digital Internal Micrometer with Bluetooth, SPC Output, 1/4-5/16" Range, .00005" Res.

The Starrett 770BXT Series Electronic Internal Micrometer, with built-in Blue tooth technology, provides IP67 level of protection against coolant, water, dirt and dust in hostile shop environments. In addition, it offers extended travel, reducing the need to exchange anvils. The ground contact points seat the internal micrometer faster and more accurately than the spherical contacts found on other gages. The rugged and accurate internal micrometer is available individually or in sets from .080"-¥ (2mm) to 12"-¥ (300mm). 1/4-5/16"-¥ (6-8mm) Range, 3-Point Carbide Contact (300mm).

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  • Wide measurement range without changing anvils
  • Carbide measuring faces on sizes above 1/2" (12.5mm) diameter
  • Extensions available for deep holes
  • Precision ratchet stop provides correct contact pressure for accurate readings
  • Each micrometer bore gage with head comes with a wooden case, complete with setting ring, contacts, adjusting wrench, spare battery, and instructions
  • IP67 level of protection against coolant, water, dirt and dust
  • Large high-contrast LCD digital readout is easy to read and reduces error
  • RS232 output
  • Includes instant inch/millimeter conversion and preset + and - functions
  • Proximity output with optional built-in Bluetooth
  • Bi-directional communication


  • Made in America: No
  • Range (in): 1/4 GÇô 5/16"
  • Range (mm): 6-8mm
  • Resolution (in): .00005"
  • Resolution (mm): 0.001mm
  • SPC Output: SPC Output
  • Approximate Measuring Depth (in): 2-1/4"
  • Approximate Measuring Depth (mm): 58mm
  • Accuracy (in): .00015"
  • Accuracy (mm): .004mm


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    California Proposition 65 Warning

      WARNING: This product can expose you to chemicals including lead, which is known to the State of California to cause cancer, and birth defects or other reproductive harm. For more information go to: www.P65Warnings.ca.gov