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