500 maH Rechargeable battery, this fan is extremely portable as no cable wiring needed which can be used both indoors and outdoors. Recharges with the provided USB charging cable. Adjust for a comfortable wind speed to suit your needs! Easy to use.This handheld fan is ideal for home, office and school, also great for travel, camping, hiking,and other outdoor activities. Its easy to carry anywhere and anytime. Your LOGO is welcome! 6.1"Lx 3.07" W x 1.97" H