Modify PP-2K 9mm GBB Rifle

Modify PP-2K 9mm GBB Rifle 1/1 Scale High Power Assembled Gas Powered Airsoft GBB Semi & Fully Automatic Shooting Mode Polymer Lower Receiver Frame Metal Upper Receiver Metal Outer Barrel With Flash Hider With 20mm Picatinny Top Rail Side Fold Metal Stock Metal Cocking Handel & Trigger Metal 22 Rounds Loading Capacity Gas Magazine Adjustable Hop-Up System