The heads are articulatable between a first plurality of relevant orientations in which {TAIL ~ a first edge} of {HEAD ~ the first head} is aligned with the first edge of the second head in a parallel spaced apart relation 
The heads are articulatable between a first plurality of relevant orientations in which { TAIL ~ a first edge } of { HEAD ~ the first head } is aligned with the first edge of the second head in a parallel spaced apart relation
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH