The grooves engage corresponding annular ridges formed {TAIL ~ adjacent the top} of the plunger when the plunger is inserted in {HEAD ~ the syringe cylinder}, preventing withdrawal of the plunger from the cylinder 
The grooves engage corresponding annular ridges formed { TAIL ~ adjacent the top } of the plunger when the plunger is inserted in { HEAD ~ the syringe cylinder } , preventing withdrawal of the plunger from the cylinder
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL 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