Features: 1. Turn any hollow core into a speaker: These bone conduction speakers are compact and versatile, allowing you to enjoy a unique sound experience in various environments. Use them with different objects to transform everyday items into functional speakers. 2. Different sounds with different surfaces: Utilizing bone conduction technology, this speaker delivers a customizable o experience. Place it on various surfaces such as glass, wood, plastic containers, photo frames, or headphones to experience a range of sound effects. 3. Portability: Lightweight and compact design makes it easy to carry and use anywhere. 4. Small but powerful speakers: When paired with suitable materials like thin plastic or hollow objects, the speaker can produce strong sound output up to 115 decibels, with adjustable sound quality. 5. Multifunctional speakers: Ideal for listening to music, podcasts, making hands-free calls, participating in conference calls, or enhancing gaming o. The built-in FM radio function allows you to tune into radio stations. Specifications: Capacity: 400mAh Function: Bone Conduction Speaker, FM Radio Wireless Version: 5.0, A2DP, HFP Supports Wireless Stereo o Built-in FM Radio Bone Conduction Transducer: 3Watt Frequency Range: 120Hz - 16kHz Built-in High-Sensitivity Microphone Battery: 400mAh Polymer Battery Charging Port: USB-C (does not support fast charging) Recommended to use FM function outdoors and connect USB cable for stable performance Material: Metal Color: Black Package Contents: 1 x Bone Conduction Speaker 1 x Charging Cable Note: Light reflection and differences in display screens may cause slight variations in color between the product image and the actual item. Measurement may vary by +/- 1-3cm.