The best replacement for calipers is micrometer.

The best alternatives to calipers are rated as following:
★★★★★  micrometer
★★★  body fat scale
★★  bia
★★  omron
★  callipers
★  rotors
★  cantilevers
★  micrometers
★  dexa
★  vernier
  brembo calipers
  dial calipers
  6 piston
  4 piston calipers
  body fat scales

Your alternative for calipers is not listed? Suggest!
Speaking about calipers, one probably shouldn't forget about avid rotors.

Other search terms related to calipers and their ratings are:
★★★★★ avid rotors
★★★★ brake pads
You have in mind a companion for calipers and it is not yet here? Propose!



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calipers
micrometer
body fat scale