This describes the SIMDET V4.01 restricted output structure, mainly intended to save disc space for reconstructed events. The output file starts with a single file header of 10 words. Each event starts with the number of energy flow objects, NEFLOW. This is followed by a series of records for each energy flow object, which describe only the best estimate of the object's energy and direction, in analogy to energy flow record 2 from the full data format, supplemented by impact parameter information.