SEA and Sky OPS Fast BJ PJ MH Helmet Balance Weight of Bag, Rapid Response Tactical Helmet Accessory Pouch Our shipping time is about 7-15 days, less than a month, sent by Beijing, China's capital. Easy to install, Unscrew the helmet behind the two large screws, install weight package the counterweight tighten A weight of about 50g, also can be equipped with batteries,Does not include demonstrate thing The helmet is equipped with arc Rrails suit, can install the battery Outdoor manufacturers to provide FMA