30dB Silent All-Night Wireless Cooling】30dB quiet operation with 10000mAh battery for all-night wireless use. It blows focused air under blankets to release heat and moisture, preventing overheating and lowering AC power costs. Heavy-Duty Height Adjustable Metal Frame】This cooling bed fan under sheets uses robust adjustable metal brackets. The height-adjust stand fixes the fan steadily under sheets, anti-shake during sleep and durable for all mattress types. 1-Minute Install & Dual Smart Control 】This Under Sheet Bed Cooling has 5 speeds, 1–6h timer, touch & remote control, wired/wireless dual power. Fast no-tool installation, height adjustable 22–53cm for precise under-bed airflow. Customized Under-Bedding Sleep Cooling】These bed fans for cooling and sleep under sheets send concentrated cool air under quilts to keep you dry. Adjustable wind relieves night sweats and uneven temperature without disturbing bed partners. Service: We place great importance on our customers' shopping experience! If you have any questions, please feel free to contact us, and we will reply within 24 hours.