Accessory Type: CoolerSpecifications: USB connectors: 4 type A connectors 1 mini USB 5-pin. Support high-speed (480 Mbps) full-speed (12Mbps) and low-speed (1.5Mbps) transfer rate. Connect up to 127 USB devices. Air Flow: 28 CFM Speed: 1500 rpm Noise Level: 25db Rated Voltage: DC 5V Power Consumption: Features: Slim & Smart design with large high-performance & quiet built-in 3 fans. Dark gray color USB 2.0 interface compatible with USB 1.1. Draw notebook's heat away and exhausts the heat through a slot. Reduce the overall temperature of your notebook. Convenient reliable & comfortable to carry. No extra driver needed for installation. Powered by USB bus.