The ultra-thin speaker placed beneath the pillow is a portable audio device specially designed to enhance the sleep experience. It is made of medical-grade silicone or flexible materials, ensuring that there is no pressure on the neck when turning over. By placing the speaker under the pillow, the sound waves are evenly transmitted through the pillow fibers, creating an immersive auditory effect similar to "bone conduction". This makes white noise, light music, or sleep-inducing audio seem to naturally emerge from the brain, effectively masking environmental noise and helping the brain quickly enter a relaxed state. Some products offer functions such as timed playback and intelligent sound effect adjustment, allowing for personalized sleep aid plans based on individual preferences. Compared to traditional bedside speakers, the ultra-thin design saves space, aligns with modern minimalist home styles, and avoids the discomfort caused by direct sound hitting the ears. Technically, it achieves wide-band sound field coverage with clear sound quality and low distortion. It is suitable for people who have long suffered from insomnia and are sensitive to sleep environments.