The polygonal rib structure 12, wherein {TAIL ~ said polygonal rib structure} is {HEAD ~ a shock absorbing member} 
The polygonal rib structure 12 , wherein { TAIL ~ said polygonal rib structure } is { HEAD ~ a shock absorbing member }
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD