THE VR72P-2SD IS DUAL 7" WIDE SCREEN LCD RACK MOUNTED UNITS 3 RACK SPACES HIGH. THE V-R72P-2SDI HAS A COMPOSITE, SDI AND S-VIDEO INPUT PER MONITOR WITH LOOPTHROUGH CAPABILITY. IN ADDITION TO THE DIGITAL AND ANALOG LOOPTHROUGHS, THIS UNIT ALSO HAS A 10-BIT CONVERTED OUTPUT FROM THE DIGITAL INPUT. THIS UNIT HAS NTSC/PAL AUTO RECOGNITION, CAN SWITCH BETWEEN 4:3 AND 16:9 ASPECT RATIOS AND HAS A BUILT-IN COLOR BAR GENERATOR AND INDIVIDUAL SELECTOR BUTTONS AND SCREEN CONTROLS.