SUITABLE FOR MOST HELMETSThrough testing, Comtac I and Comtac II headset can be perfectly paired with this headset adapter. And it can fit with a whole range of FAST helmets, ACH helmet, MICH helmet as long as they have arc rails on the side COMFORTABLE FOR USEDrastically improves the comfort and protection of your helmet, you must no more struggling for space in your helmet or removing helmet pads to fit a headset SPECIAL DESIGNWhen hanging after the Comtac Intercom Headset, the headset is pulled out of the arc-shaped headband, located on the map directly at the Hanging chain used ROTATE FREELYHang buckle can be attached to the 2 sides of the helmet rails on the helmet, after installation, the Comtac headphone headset can rotate freely EASY ASSEMBLYRequire Do some assembly, mainly removing the earmuffs from the headband and then snapping them to the adapters