The apparatus comprises an elongate base having means on one end for mounting the base on a laboratory ring stand and {TAIL ~ means} on the other end of the base for allowing {HEAD ~ a technician} to hold the microcentrifuge tube in one hand and to open and close the cap without requiring a second hand 
The apparatus comprises an elongate base having means on one end for mounting the base on a laboratory ring stand and { TAIL ~ means } on the other end of the base for allowing { HEAD ~ a technician } to hold the microcentrifuge tube in one hand and to open and close the cap without requiring a second hand
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