Interface cable to connect your Ward's Sniper Mk. III head unit to a Preston MDR2, MDR3, or MDR4 Serial port, displaying the readout data from the Sniper on your HU3. Your head unit must have the appropriate firmware installed from the factory for this cable to function. These cables are wired differently from Display cables, and operate in one direction only. It is important to note this cable only works in one direction. The correct installation of this cable is with the 90-degree connector going into your head unit, and the straight connector going into the Serial port of your MDR. This cable will not work when connecting a Sniper display to the head unit.