WE Adaptive Cylinder (450FPS) for WE KATANA M4 AEG Series (Grey)

WE Adaptive Cylinder (450FPS) for WE KATANA M4 AEG Series (Grey)
http://airsoft.tiger111hk.com/p22187/WE-Adaptive-Cylinder-%28450FPS%29-for-WE-KATANA-M4-AEG-Series-%28Grey%29/product_info.html