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ICS Complete Reinforced M120 Upper Gearbox Set - For M4 AEGs

SKU: DSI-MA-54 ICSOut of stock

  • Upgrades muzzle velocity to 420 FPS (w/ 0.20g BBs)
  • Aluminum full teeth piston
  • Version 2 reinforced air nozzle
  • ICS M4 tappet plate
  • Version 2 ball bearing spring guide
  • Reinforced aluminum ball bearing piston head
  • Reinforced aluminum cylinder / cylinder head
  • Easy-to-install, complete upper gearbox set
  • Compatible with ICS split gearbox AEGs only


In the Box

ICS M4 upper gearbox shell



piston head

cylinder head

air nozzle

spring guide

tappet plate




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