Maple Leaf Humming Brid Short-Stroke Bolt Assembly For GHK M4 GBB Rifle Airsoft Gun

Maple Leaf Humming Brid Short-Stroke Bolt Assembly For GHK M4 GBB Rifle Airsoft Gun Metal Construction Airsoft Bolt Assembly Design For Upgrade your Original Airsoft Guns Parts Able to Increase the Cyclic Rate of Your Airsoft GBB Rifle Suitable For GHK M4 Series Gas Blow Back GBB Airsoft Rifle