Nitecore Portable Electronic Repeller. Mosquito repelling function. Ultrasonic function. Power supply. Comes with 10 mosquito repellant mats. Heat insulation guard. OLED real-time display. Water proof. 12 hour max runtime. Requires (2) 21700 batteries (included). Boxed. Specifications for Nitecore Portable Electronic Repeller: Manufacturer: Nitecore Age Group: Adults Length: 5 in Weight: 0.88 lb Overall Length: 5 in Package Contents: Nitecore Portable Electronic Repeller