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 functional speakers with ease. 2. Different sounds with different surfaces: Utilizing bone conduction technology, this speaker delivers a customizable audio experience. Sound quality varies when attached to different materials such as glass, wood, plastic containers, photo frames, or headphones, allowing you to explore diverse acoustic effects. 3. Portability: Lightweight and compact design makes it easy to carry and use anywhere. 4. Small but powerful: When attached to suitable surfaces like thin plastic or metal objects, the speaker can produce strong sound output up to 115 decibels, with adjustable sound characteristics. 5. Multifunctional use: Supports music playback, podcasts, hands-free phone calls, conference calls, gaming audio, and FM radio reception. Built-in FM radio allows direct access to radio stations. Specifications: Capacity: 400mAh Functions: Bone Conduction Speaker, FM Radio Wireless Version: 5.0, A2DP, HFP Stereo Audio 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 (no fast charging support) Note: For optimal FM performance, use outdoors and connect the USB cable during FM operation. Material: Metal Color: Silver Package Contents: 1 x Bone Conduction Speaker 1 x Charging Cable Note: The product image may slightly differ in color due to lighting and screen settings. Measurement tolerance: +/- 1-3cm.