Voltage selection: Can be directly in the product back label, or the power supply of the product can be seen, there are power input 5V standards, according to your router to choose our corresponding boost line. (12V boost line output 1A, if you are more than 1A, you can't use it) Most routers that can be directly outside are 5.5 x inside diameter 2.1. Power plug size specifications: If you are not sure, you can consult the manufacturer of the equipment, or consult the merchant who sells the equipment online: whether the size of the power DC plug is 5.5 x outside diameter 2.1mm, if you are please choose. 12V boost line: with boost components, the USB input 5V voltage through the components, boosted to 12V voltage 1A, Weight: 0.110231131 pounds, Manufacturer: ximie