The second member is removable from {HEAD ~ the channels} by pulling the second member away from {TAIL ~ the channels} to disengage the flanges from the channels 
The second member is removable from { HEAD ~ the channels } by pulling the second member away from { TAIL ~ the channels } to disengage the flanges from the channels
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH