a deformable connecting interface between the axle and the guide arm which, because of a deformable nature, facilitates lateral displacement of {HEAD ~ the axle} relative to {TAIL ~ the guide rail} ; and 
relative to
a deformable connecting interface between the axle and the guide arm which , because of a deformable nature , facilitates lateral displacement of { HEAD ~ the axle } relative to { TAIL ~ the guide rail } ; and
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 REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH