The best replacement for cat 5 is cat 6.

The best alternatives to cat 5 are rated as following:
★★★★★  cat 6
★★★★  cat 6 cable
★★★  cat 5e
★★★  6
★★★  cat 3
★★  5e
★★  cat5e
★  cat 7
★  coax
★  cat 6 ethernet cable
★  cat6
★  cat 6 ethernet
★  cat 6 network cable
★  6 cable
★  cat 7 cable
★  cat 5e cable
  cat 6 cables
  fiber
  cat 6 wiring
  cat 6a
  rj45
  cat 6 cable category 6
  cat 6 connector
  phone line

Your alternative for cat 5 is not listed? Suggest!
Speaking about cat 5, one probably shouldn't forget about rj11.

Other search terms related to cat 5 and their ratings are:
★★★★★ rj11
You have in mind a companion for cat 5 and it is not yet here? Propose!



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cat 5
cat 6
cat 6 cable