Professional NBU Tune-up Kit for M4 - M150

Professional upgrade set with the NBU air set. Include all parts for your succes upgrade. Dedicated for the M4 AEG. Recommended barrel 300-400 mm. Set include:

• Stainless steel cylinder - NBU
• Polycarbonate back pressure silent piston head with the bearing
• Stainless steel cylinder head with double O-rings
• Acetal nozzle with O-ring
• Light polycarbonate piston with the full metal teeth.
• M150 spring
• Stainless steel spring guide with the bearing.
• Hi torque gear set
• Shims and springs set
• Antireversal latch with the spring
  
• Tappet plate