RECHARGEABLE DESIGN: Permanent, rechargeable batteries enable up to 17 hours of run time (on low) and re-charge in just 3.5 hours. THREE SPEEDS: Choose high speed to deliver invigorating airflow, or low speed for more quiet, personalized airflow. PORTABLE CONVENIENCE: Its compact size and cordless design allows for a seamless transition between your workspace and your workout. SATISFYING SOUND: The optimized sound signature creates an enhanced and relaxing enviornment to help you focus in your space. SUPERIOR SUPPORT: Supported by a customer service team based in Andover, KS. Built to meet U. S. voltage requirements. Certified, safety-tested, and warrantied for use only in the U. S