Check the listing for details. FMA helmet accessories PVS31 IR infrared strobe battery box function version. Condition: New. Listed at 81.10 USD. picture display product description Product features The 4-pin aviation connector is used for point-to-point positioning, anti-skid insertion and dialing. It is used with gsgm support to support the power supply of a variety of night vision instruments Four No. 5 standard AA batteries can be placed in the battery compartment at the same time, numbered 1.2.3.4 from left to right, of which No. 1.2 is group A, No. 3.4 is group B, and group A and group B are in series structure. At least one battery in each group is required to work normally and output current. The output voltage of the battery box is the sum of the highest single battery voltage in group A and the highest single battery voltage in group B, The output voltage needs to be controlled between 2.0v-3.5v.