Along the body 8 is a plurality of lateral, crescent shaped grooves 10, 12, disposed on {HEAD ~ opposite sides} of {TAIL ~ the device} in alternating fashion 
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Along the body 8 is a plurality of lateral , crescent shaped grooves 10 , 12 , disposed on { HEAD ~ opposite sides } of { TAIL ~ the device } in alternating fashion
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 TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH