The battery slots indicate the charging positions of CD batteries and AA AAA batteries, so don't worry about not knowing how to use. 1-2 PC 1100mah AA/AAA batteries-- about 1H; 1-2 PC 2800mah AA battery--about 3H; 4-8 PC 1100mah AA/AAA battery--2H-4H;.

Brand: Bonai
Compatible Battery Sizes: AA, AAA, C, D
Type: USB
Product Dimensions: 3.94"D x 5.71"W x 1.4"H
Output Voltage: 1.4 Volts
Item Weight: 200 Grams