f) said buffer means comprising an impeller immersed in said viscous fluid for use as {TAIL ~ a brake} of said closing means; whereby said buffer means reduces rotational speed of said reel thus reducing closing speed of {HEAD ~ said door} 
f ) said buffer means comprising an impeller immersed in said viscous fluid for use as { TAIL ~ a brake } of said closing means ; whereby said buffer means reduces rotational speed of said reel thus reducing closing speed of { HEAD ~ said door }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH 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 HEAD HEAD HEAD HEAD HEAD HEAD