Yes this is the ONLY side support, the clip fits in a triangular hole and will/should be nice and tight, the slot that the bumper knob bit goes into should be solid with no movement, then a BOLT passes through from the inner wing area through the hole in the centre of the lot to a captive insert in the side support bracket of the bumper.
Often(read ALWAYS!!) these inserts/bolts jam together, so use a SS bolt with coppaslip to prevent it happening again.
tabetha