As described above, since the metallic parts 11 and 21 will automatically roll to assume the transverse position, what is more advantageous is that the metallic parts rotate of themselves relative to each other until the flanges extend along {HEAD ~ the curve} of the body, so that {TAIL ~ the clasp} snugly fits on the curve of the body 
As described above , since the metallic parts 11 and 21 will automatically roll to assume the transverse position , what is more advantageous is that the metallic parts rotate of themselves relative to each other until the flanges extend along { HEAD ~ the curve } of the body , so that { TAIL ~ the clasp } snugly fits on the curve of the body
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 OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH