In {TAIL ~ an obturator} comprising a forwardly tapered male plug with a shaft extending from the forward end thereof, said plug including locking means for releasable engagement with projecting dogs on {HEAD ~ a catheter fitting} having an inwardly tapered smooth female portion upon insertion of the obturator into the catheter fitting, the improvement comprising: 
In { TAIL ~ an obturator } comprising a forwardly tapered male plug with a shaft extending from the forward end thereof , said plug including locking means for releasable engagement with projecting dogs on { HEAD ~ a catheter fitting } having an inwardly tapered smooth female portion upon insertion of the obturator into the catheter fitting , the improvement comprising :
OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH 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 HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH