Adder SmartView SVMS4-S 4 port PS2 and single head video and RS232 KVM switch features high quality video with DDC support and resolutions up to 1920 by 1440 pixels. It allows complete and  transparent switching for all RS232 serial lines (in unison with keyboard, video and mouse channels). It also offers increased switching capabilities where more video monitors are required, you can synchronize two units together to support twice the number of video and serial channels. Manual