1. No indicator light, no external power supply, suitable for desktop computers and laptops 2. Support hot swap, low power consumption, the product is suitable for U disk, card reader, USB mouse, USB keyboard, scanner, digital camera 3. Digital video camera, USB sound card, hard disk box, etc., expand 4 USB ports, each power supply up to 500Ma, use USB HUB controller, no driver, plug and play, support hot swap, can support 127 USB device 4. Transmission interface: support USB2.0 compatible with USB1.1 5. Operating system: Win95 osR2/98SE/Me/2000/XP, Linux2.4 and Mac OS 8.5 VASTA and above 6. Transmission rate: speed up to 480Mbps 7. Power supply: USB 5V/600mA 8. External power supply: 5V/1.5A-2A