{HEAD ~ The grooves} on the front end of device face proximally and are disposed on {TAIL ~ opposite sides} of the device in alternating fashion 
are disposed on
{ HEAD ~ The grooves } on the front end of device face proximally and are disposed on { TAIL ~ opposite sides } of the device in alternating fashion
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH