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. Use them to transform everyday objects into audio sources. 2. Different sounds with different surfaces: Utilizing bone conduction technology, this speaker delivers a customizable audio experience. Place it on surfaces such as glass, wood, plastic containers, photo frames, or headphones to experience varied sound outputs. 3. Portability: Lightweight and compact design makes it easy to carry and use anywhere. 4. Small but powerful: When paired with suitable materials, the speaker can produce strong sound output, reaching up to 115 decibels, with customizable sound quality. Best performance is achieved on thin, resonant materials. 5. Multifunctional use: Supports music playback, podcasts, hands-free calls, conference calls, gaming, and movie audio. Built-in FM radio functionality allows for listening to radio stations and audio content. Specifications: Capacity: 400mAh Function: Bone Conduction Speaker, FM Radio Wireless Version: 5.0, A2DP, HFP Supports Wireless Stereo Built-in FM Radio Bone Conduction Driver: 3Watt Frequency Range: 120Hz - 16kHz Built-in High-Sensitivity Microphone Battery: 400mAh Polymer Battery Charging Port: USB-C (not compatible with fast charging) Recommended to use FM function outdoors; connect USB cable for optimal performance Material: Metal Color: Black / Red / Silver Package Contents: 1 x Bone Conduction Speaker 1 x Charging Cable Note: Light reflection may affect appearance in images.