Reminder: This product only connects to positive and power supply,and the output depends on the adapter used. Users who choose router heat dissipation racks,they already have a 12V,9V,or 5V power supply,can use this dedicated adapter cable to power the heat dissipation rack and solve networkequipment heat dissipation problems. It is common to adapt to 12V or 9V 5V1A power supplies,and devices such as surveillancecameras,routers,andADSL cats are mostly used Product function: Change the chassis computer fan to DC5521 power supply,please select this line. The new design features a bold DC5521 metal seat,a fan connector,and a needle seat welding wire forinjection molding