The OEM bumper includes backup sensors that work with the standard prisoner transport rear step, but the sensors detect the optional flip step when it is in the stowed/closed position. The flip step can be used; however, it will require the driver to push the OEM sensor deactivation switch every time the van is in reverse. In addition to the sensor issue, the ProMaster cargo floor is lower to the ground than other vans, because it has front wheel drive, which allows the cargo floor to be lower. If the flip step where used, it would be approximately 5″ off the ground.