Features: 1. Turn any hollow surface into a speaker: These bone conduction speakers are compact and versatile, delivering an immersive sound experience in various environments. Use them on different surfaces to enjoy unique audio output. 2. Unique sound on different materials: Utilizing bone conduction technology, this speaker allows you to experiment with sound by attaching it to various surfaces such as glass, wood, plastic containers, photo frames, or headphones, each creating a distinct audio effect. 3. Portable design: Lightweight and compact, this speaker is easy to carry for use at home, outdoors, or on the go. 4. Powerful sound performance: When placed on resonant surfaces like thin plastic containers or boxes, the speaker can produce strong, clear audio up to 115 decibels, offering customizable sound quality. 5. Multi-functional use: Enjoy music, podcasts, phone calls, conference calls, gaming, or movies with this versatile speaker. It also supports FM radio functionality for listening to broadcasts. Specifications: Capacity: 400mAh Functions: Bone Conduction Speaker, FM Radio Wireless Version: 5.0, A2DP, HFP Supports Wireless Stereo Audio Built-in FM Radio Bone Conduction Transducer: 3W Frequency Range: 120Hz - 16kHz Built-in High-Sensitivity Microphone Battery: 400mAh Polymer Battery Charging Port: USB-C (no fast charging support) Recommended to use FM function outdoors; connect USB cable for stable performance Material: Metal