Description of products: 1). The sound emited by the product can only be heard by mosquito, it' s hurtless to home electrical appliances, human and pets.   2). The product is steady and effective. You will get evident effect once use it. And you will drive all the disgusting mosquito out after 5-7 days' continuous use.   3). It has three buttons, turn the buttons can change the frequency have better effective with the pest. When the button in the " dragonfly", that emit sound like dragonfly' s wing repel mosquitoes; when the button in the " Mosquito|", that emit sound like mosquite' s wing in a frequency repel female mosquitoes; When the button in the  " Mosquito||", that emit sound like mosquite' s wing in another    frequency repel female mosquitoes. UL Packing Details: QTY: 24PCS/CTN N. W.: 3.0KGS G. w.: 4.0KGS MEAS: 33*32*38.5CM GS Packing Details: QTY: 24PCS/CTN N. W.: 3.2KGS G. w.:  4.2KGS MEAS: 32.5*34.5*39CM