3. Built in 21700 lithium battery, with long battery life and up to 4 hours of low-frequency use. 1.140000 RPM turbofan, brushless motor, powerful. 2. Strong dust removal, handling a series of debris such as accumulated dust, sand, hair, etc. 4. Infinite speed regulation, easy to operate with one hand, two in one switch speed regulation, increasing air volume from small to large, better protecting the motor., Manufacturer: Ounfhtrttk