said {HEAD ~ first and second openings} having cross {TAIL ~ sectional configurations} of a type to allow passage of said keeper element therethrough, 
having
said { HEAD ~ first and second openings } having cross { TAIL ~ sectional configurations } of a type to allow passage of said keeper element therethrough ,
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH