A helical spring is received in, and actually extends into, a blind hole in each stem, and the inner end of the spring rests on the retaining ring at {HEAD ~ the projection} urging {TAIL ~ the blades} outward 
urging
A helical spring is received in , and actually extends into , a blind hole in each stem , and the inner end of the spring rests on the retaining ring at { HEAD ~ the projection } urging { TAIL ~ the blades } outward
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 REL TAIL TAIL TAIL TAIL TAIL TAIL OTH