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StarTech.com 4-to-1 USB 2.0 Peripheral Sharing Switch (USB421HS)

Share a high speed USB 20 device with up to 4 computers and easily switch between them through push-buttons keyboard hot-key commands or software
A compact desktop form factor and no external power requirement makes for an easy to use and portable data switch
Backed by a StarTechcom 1-year warranty and free lifetime technical support
Push-button hot-key controls or software for switching between computers
Compliant with the USB 20 standard with data transfer rates up to 480Mbps
Powered directly from the USB port