SIR Unit (rail system) for M4s

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  • Regular price $79.99

  - Attaches to AR-15 style rifle upper receiver flat top rail
  - Free float quad-rail designs full of 20mm picatiny rails
  - No stress on outer barrel
  - Regular triangular front sight can remain on outer barrel, or removed.
  - Handguard can only hold a short stick 3 cell Lipo battery