The best replacement for hpa is co2.

The best alternatives to hpa are rated as following:
★★★★★  co2
★★★★  inhg
★★  mb
★★  kpa
★★  co2 paintball
★★  lpa
★  mbar
★  n2
★  nitrogen
★  eip
★  compressed air
★  hpi
  nitrogen paintball
  konawaena
  co2 a5

Your alternative for hpa is not listed? Suggest!
Speaking about hpa, one probably shouldn't forget about tippmann a-5.

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



Google Trends

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hpa
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