The counter weight comes in a bag, special made for attaching to FAST and OPS-Core helmets. It is designed with 5 weights of 55g which allows you to adjust the weight to counter the weight of different sizes of NVG. It is mounted on the back of the helmet for stability.
Info:
Model: Counter Weight
Size: 120 x 45mm
Weight: 85g - 306g
Colour: Black
