This read-write Integer32 specifies the average frame size assumed before fragmentation for accounting purposes on an F3 network port's QoS shaper. An administrator sets it so the shaper's rate calculations correctly account for overhead introduced when frames are fragmented before transmission. For example, on a port where large frames are routinely fragmented for a TDM-encapsulated link, tuning this value keeps the shaper's enforced rate accurate despite the added per-fragment overhead.