It is also contemplated in this embodiment that the pen cartridge may be extended as a result of {HEAD ~ a pressure} applied to {TAIL ~ the edges} of the housing 
applied to
It is also contemplated in this embodiment that the pen cartridge may be extended as a result of { HEAD ~ a pressure } applied to { TAIL ~ the edges } of the housing
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 OTH OTH OTH