The best replacement for rj45 is rj48.

The best alternatives to rj45 are rated as following:
★★★★★  rj48
★★★★★  cat5
★★★★  rj11
★★  cat6
★★  8p8c
★★  rj12
★  rs232
★  rj45m
★  cat5 cable
★  rs485
★  rj48 connector
★  rj25
★  rj 485
★  sfp
★  utp
  ethernet cable
  rj 14
  cat5e
  rj47
  rj-45
  rj45
  rj46
  cat 5
  bnc
  rj48c

Your alternative for rj45 is not listed? Suggest!
Speaking about rj45, one probably shouldn't forget about cat6.

Other search terms related to rj45 and their ratings are:
★★★★★ cat6
You have in mind a companion for rj45 and it is not yet here? Propose!



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rj45
rj48
cat5