an air flow passage through which {HEAD ~ grass cuttings} are discharged from said cutting chamber in a current of {TAIL ~ air} 
an air flow passage through which { HEAD ~ grass cuttings } are discharged from said cutting chamber in a current of { TAIL ~ air }
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL