{TAIL ~ A retainer} is used for securing {HEAD ~ the skylight cover} over the operating leaf frame 
{ TAIL ~ A retainer } is used for securing { HEAD ~ the skylight cover } over the operating leaf frame
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH