This wireless helmet speaker has a compact body, with a diameter of only 46mm and a thickness of 15mm. It is suitable for most ski helmets and cycling helmets. What's more classic is that this headset is equipped with a sports helmet headscarf, which means that the headset can also be used without a helmet, because the headscarf is specially developed for this headset. There are two headphone holes at the internal measuring opening of the headscarf. You can put the headset into the headscarf so that you can use it for running, or you can wear it directly on the helmet (use the headset without ear protection) for cycling, skiing, and other outdoor sports. Experience the perfect fusion of music and safety on the slopes with ski helmet headphones. These innovative audio accessories integrate seamlessly into your ski helmet, allowing you to enjoy your favorite tunes while carving through the powder. The sleek design ensures a secure and comfortable fit, while the high-quality speakers deliver crystal-clear sound that won't distract you from the thrill of the ride. Whether you're a seasoned pro or a beginner, these headphones will elevate your skiing experience to new heights. Tune in to the rhythm of the mountain and let the melodies guide your every turn. The M Jiuyunmu Wireless Bluetooth headphones adopt the latest Bluetooth 5.3 to maintain a stable connection within ten meters and a faster transmission speed. As a result, you can enjoy conversations and music with no audio dropouts or interruptions.keep you going while mountain biking, climbing, skiing, and snowboarding.