The annular space between the internal lateral wall of the cone frustrum allows a relative lateral displacement and of {TAIL ~ at least one damping ring} secured or not secured to the internal lateral wall of the circular cap and {HEAD ~ the lateral wall} of the cone frustrum 
The annular space between the internal lateral wall of the cone frustrum allows a relative lateral displacement and of { TAIL ~ at least one damping ring } secured or not secured to the internal lateral wall of the circular cap and { HEAD ~ the lateral wall } of the cone frustrum
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL 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