Features: 1. Turn any hollow core into a speaker: These bone conduction speakers are compact and versatile, enabling a unique o experience in various environments. Transform any hollow surface into a speaker anytime, anywhere. 2. Different sounds with different surfaces: Utilizing bone conduction technology, this speaker delivers a customizable o experience. Experiment with various surfaces such as glasses, guitars, paper boxes, plastic containers, photo frames, headphones, or dashboards to enjoy distinct sound effects. 3. Portability: Designed with a small size and lightweight build, this speaker is easy to carry and use on the go. 4. Small but powerful: When attached to suitable objects, the bone conduction speaker can produce strong sound output up to 115 decibels, allowing for personalized sound quality. It is recommended to use thin materials like plastic boxes or buckets for optimal performance. 5. Multifunctional use: Use the bone conduction speaker for listening to music, podcasts, making hands-free phone calls or conference calls, playing games, and enhancing gaming o. The built-in FM radio function allows you to tune into radio stations and enjoy o content. 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 (not compatible with fast charging) Recommended to use FM function outdoors; connect USB cable during use. Material: Metal Color: Silver Package Contents: 1 x Bone Conduction Speaker 1 x Charging Cable Note: Light reflection and differences in display screens may cause slight variations between the color of the item in images and the actual product. Measurement tolerance allowed is +/- 1-3cm.