For modern milsim events I use a replica of the well-known Fast Helmet. The helmet is open in the side area and allows the use of headphones. It also has an NVG mounting platform at the front, where I use a Runcam 5 to record games. The PJ variant already has air inlets that serve for better air circulation inside the helmet. On the side, the helmet has mounting rails for other accessories such as lamps, or mask holders. Since I play it in conjunction with paintball masks, I had to make some changes to the suspension system, padding and straps.