{HEAD ~ At least one glow rod} has {TAIL ~ a contact part} that is spring mounted at the glow rod in an axially displaceable fashion 
{ HEAD ~ At least one glow rod } has { TAIL ~ a contact part } that is spring mounted at the glow rod in an axially displaceable fashion
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH