To lock {TAIL ~ the parts} in place the lower tongues are each formed with a downwardly extending hook projection which is in interfering engagement with the lower edge, or ledge, of the window, making {HEAD ~ the cross beams} captive against longitudinal withdrawal from their seated positions 
To lock { TAIL ~ the parts } in place the lower tongues are each formed with a downwardly extending hook projection which is in interfering engagement with the lower edge , or ledge , of the window , making { HEAD ~ the cross beams } captive against longitudinal withdrawal from their seated positions
OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH 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 OTH OTH OTH OTH OTH OTH OTH OTH