The VS-491 provides electronic switching for greater reliability and durability. It displays the output of four computers on a single monitor with high resolution video - up to 1920 x 1440; DDC2B. It supports, VGA, SVGA, XGA and multisync monitors. Computer selection is performed via pushbutton switch. Aten VS491 4-Port Video Switch is one of many Switchboxes available through Office Depot. Made by Aten.