I have two fans attached to the bolts of the aerators run by a 9v battery. What you cant see is the battery boxes which I have mounted on either side by the ears and the small amp is velcroed in the top of the helmet, which is also run by a 9v. Seem to be working great for me, this is an AP helmet so I had limited space to work with. It is a little snug to get on and off, but feels really comfortable when its on. Since taking this picture I have added screens to the fans for obvious reasons lol
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