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 16 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).