The door construction 7 wherein the block of resilient material includes {HEAD ~ a recess} for {TAIL ~ engagement} by the ball bearing 
for
The door construction 7 wherein the block of resilient material includes { HEAD ~ a recess } for { TAIL ~ engagement } by the ball bearing
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH