Airsoftjunkiez expand their customised HPA-powered ASG Scorpion EVO 3A1 with a version that uses the PolarStar Airsoft Jack HPA engine. This uses the BlackLeaf Airsoft ASG Scorpion EVO HPA Trigger Board and FCU Kit that is compatible with PolarStar and Redline engines and FCU to allow SEMI/BURST/AUTO and comes with an MCU Wire for Burst.