To define a stable position of the draft shield element on the sample changer, {HEAD ~ the seating rim} of the draft shield element sits in {TAIL ~ a matching seating recess} of the sample changer 
sits in
To define a stable position of the draft shield element on the sample changer , { HEAD ~ the seating rim } of the draft shield element sits in { TAIL ~ a matching seating recess } of the sample changer
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 REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH