Description
H&K HK MR556 A4 Gas Block – Complete
Factory HK MR556 A4 adjustable gas block ideal for switching between suppressed and unsuppressed firing.
Compatible With:
- HK MR556 A4
- Nefarious Arms A5 barrels
- NOT compatible with MR556 A1 without converting to an A4 or Nefarious Arms barrel.
Features:
- 1.3mm vent screw
- Genuine H&K factory part
- Complete gas block assembly
- Durable construction for long service life
- Ideal for replacement, upgrade, or custom builds
