CYMA Plastic Reinforced Hop Up Chamber Set For CYMA Tokyo Marui SL8 SL9 UMP G36 Series AEG Rifles AirsoftCYMA Plastic Reinforced Hop Up Chamber Set For CYMA Tokyo Marui SL8 SL9 UMP G36 Series AEG Rifles Made out of plastic. Improves Firmness of the chamber and stabilizes the muzzle velocity. Fit tightly to the barrel base to keep the chamber being centered. Suitable for CYMA Tokyo Marui SL8 SL9 UMP G36 Series AEG Rifles. Color Black Weight 10g Original Packing.