A well tuned hop-up is crucial for accuracy.
Nine Ball GBB Barrel
Nine Ball MP7 AEP 6.03mm Steel Barrel 182mm
Nine Ball Wide Use Soft Purple Bucking/Packing for VSR-10 and TM GBBs
Prometheus EG Barrel 6.03mm
Prometheus NEO Metal Hop Up Unit for M4/M16 Series AEGs
Prometheus NEO Metal Hop Up Unit with hop arm + cam for M4/M16 Series AEGs