The best replacement for g pen is atmos.

The best alternatives to g pen are rated as following:
★★★★★  atmos
★★★★  cloud
★★★★  pax
★★★★  micro g
★★★  omicron
★★  mflb
★★  atmos jr
★★  trippy stick
★★  cloud vape
★  trippy stix
★  cloud 2.0
★  magic flight
★  microg
  g pen
  cloud pen
  cloud vape pen
  g pen micro
  dr dabber

Your alternative for g pen is not listed? Suggest!
Speaking about g pen, one probably shouldn't forget about bubble hash.

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



Google Trends

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g pen
atmos
cloud