{HEAD ~ The plunger} 20 is preferably a standard syringe plunger formed of Polystyrene or {TAIL ~ Polypropelene} and comprises a shaft 26 having a cross section which is a cruciform, i.e. X shaped, as best illustrated in FIG 4 
{ HEAD ~ The plunger } 20 is preferably a standard syringe plunger formed of Polystyrene or { TAIL ~ Polypropelene } and comprises a shaft 26 having a cross section which is a cruciform , i.e. X shaped , as best illustrated in FIG 4
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH 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