Features: 1. Turn any hollow core into a speaker: These bone conduction speakers are the smallest and most versatile bone conduction speakers in the world, allowing you to enjoy a unique sound experience in any environment. Transform any hollow surface into a speaker anytime, anywhere. 2. Different sounds with different surfaces: This speaker uses bone conduction technology to deliver a customizable o experience. You can test and enjoy varied sound outputs—similar to using different instruments. Placing it on various surfaces such as glasses, guitars, paper boxes, plastic containers, photo frames, sports headphones, or dashboards can produce a range of sound effects. 3. Portability: This product is compact and lightweight, making it easy to carry. 4. Small but powerful speakers: When paired with the right object, these bone conduction speakers can deliver strong o output, reaching up to 115 decibels, with customizable sound quality. It is recommended to use thin materials such as plastic boxes or buckets for optimal performance. 5. Multifunctional speakers: Use the bone conduction speaker for listening to music, podcasts, making hands-free phone calls or conference calls, playing games or movies, and enhancing your gaming o experience. The speaker also functions as an FM radio, enabling you to listen to radio stations and o content. Specifications: Capacity: 400mAh Function: Bone Conduction Speaker, FM 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 and connect USB cable during use. Material: Metal Color: Black / Red / Silver Package Contents: 1 x Bone Conduction Speaker 1 x Charging Cable Note: Only the items listed above are included; other products are not included.