The KH2508A KVM switch is a control unit that allows IT administrators to access and control multiple computers from two PS/2 or USB KVM consoles (one bus). Operators working at up to two consoles can independently and simultaneously take control of up to 8 computers. By daisy chaining up to 15 additional switches, as many as 128 computers can be controlled from the original KVM consoles. Superior Video Quality- Supports the video resolutions up to 1920 x 1200 @60Hz for up to 30 meters, 1600 x 1200 @60Hz for up to 40 meters, and 1280 x 1024 @75Hz for up to 50 meters. Three port selection methods: Manual (via front panel pushbuttons), Hotkey, and multi-language OSD (On Screen Display).