Professional helmets earphones installation rail adapter accessories, which make it more comfortable and convenient to use earphones when wearing helmets. Features: Fine quality ABS material, practical and wearable, can use for a long time. Multi-angle rotation. The connecting arm installed on the headset can realize 360 rotation of the headset. When the headset not use, It can be folded outward or back to the helmets. More convenience. The headset is not easy to drop and is more convenient to use. The telescopic design of the connecting arm makes it easy to adjust the headset to a comfortable position. Specifications: Color: black, mud, green (optional) Material: ABS Package size: 130 * 105 * 45mm / 5.1 * 4.1 * 1.8in Package weight: 200g / 7.1ounce Packing List: 2 * Connecting Arm 2 * Rubberrings 1 * Set of Screws 1 * Wrench 2 * Adapter 1 * Screwdriver