Also on its downstream side each fly weight 22 has {TAIL ~ a cylindrical rebate} 27 at its radially inner edge which receives a cylindrical upstream projection 28 of {HEAD ~ the nut} 18 
Also on its downstream side each fly weight 22 has { TAIL ~ a cylindrical rebate } 27 at its radially inner edge which receives a cylindrical upstream projection 28 of { HEAD ~ the nut } 18
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH