a stiffener defining an opening in a central portion thereof and having front and rear ends, the stiffener having {HEAD ~ an locking hook} close to {TAIL ~ the front end} along a first side of the stiffener 
close to
a stiffener defining an opening in a central portion thereof and having front and rear ends , the stiffener having { HEAD ~ an locking hook } close to { TAIL ~ the front end } along a first side of the stiffener
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH