The best replacement for gas block is gas piston.

The best alternatives to gas block are rated as following:
★★★★★  gas piston
★★★★  no gas block
★★★  front sight
★★★  steel
★★  set screw
★★  .750
★★  steel gas block
★  4 rail gas block
★  fsb
★  .936
★  set gas block
★  low profile

Your alternative for gas block is not listed? Suggest!
Speaking about gas block, one probably shouldn't forget about flip up sight.

Other search terms related to gas block and their ratings are:
★★★★★ flip up sight
★★★★★ front sight
★★ folding front sight
★★ flip up front sight
★★ sling swivel
★ folding sight
You have in mind a companion for gas block and it is not yet here? Propose!



Google Trends

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gas block
gas piston
no gas block