Features: 1. Turn any hollow core into a speaker: These bone conduction speakers are compact and versatile, enabling a unique sound experience in various environments. Transform everyday objects into speakers with ease. 2. Different sounds with different surfaces: Utilizing bone conduction technology, this speaker delivers a customizable audio experience. Experiment by placing it on various surfaces such as glass, wood, plastic containers, photo frames, or headphones to achieve distinct sound effects. 3. Portability: Lightweight and compact design makes it convenient for travel and daily use. 4. Small but powerful: When paired with suitable materials like thin plastic or hollow objects, the speaker can produce strong audio output, reaching up to 115 decibels, with adjustable sound quality. 5. Multifunctional use: Ideal for listening to music, podcasts, making hands-free calls, participating in conference calls, gaming, or enhancing audio immersion. Built-in FM radio allows for direct radio playback. Specifications: Capacity: 400mAh Functions: Bone Conduction Speaker, FM Radio Wireless Version: 5.0, A2DP, HFP Stereo Wireless Support: Yes Built-in FM Radio: Yes Bone Conduction Transducer: 3Watt Frequency Range: 120Hz - 16kHz Built-in High-Sensitivity Microphone: Yes Battery: 400mAh Polymer Battery Charging Port: USB-C (does not support fast charging) Note: For optimal FM performance, use outdoors and ensure the device is powered via USB cable. Material: Metal Color: Black Package Contents: 1 x Bone Conduction Speaker 1 x Charging Cable Note: The product image may differ slightly in color due to lighting and screen settings. Measurement may vary by ±1-3cm.