{TAIL ~ The filter body} is rotatable around {HEAD ~ the axle}, which is permeable to the x ray radiation 
{ TAIL ~ The filter body } is rotatable around { HEAD ~ the axle } , which is permeable to the x ray radiation
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH