Description
  • For GBB Inner Barrel
  • Anti-frozen silicone material

 

         50 degree (green) for muzzle velocity below 110 m/s

  • 60 degree (yellow) for muzzle velocity 90-120 m/s
  • 70 degree (blue) for muzzle velocity 110-140 m/s
  • 80 degree (RED) for muzzle velocity over 150 m/s