The best replacement for cat 3 is cat 5.

The best alternatives to cat 3 are rated as following:
★★★★★  cat 5
★★★★★  cat 5 cable
★★  cat 5e
★  cat 5 wire
★  rj11
★  cat5
  cat 4

Your alternative for cat 3 is not listed? Suggest!
Speaking about cat 3, one probably shouldn't forget about rj11.

Other search terms related to cat 3 and their ratings are:
★★★★★ rj11
You have in mind a companion for cat 3 and it is not yet here? Propose!



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cat 3
cat 5
cat 5 cable