The filter 11 is coaxially housed in an outer cylindrical casing 4 with a gap 14 provided within the casing and is retained by {TAIL ~ a pair} of {HEAD ~ front and rear shielding plates} 17 and 18 
The filter 11 is coaxially housed in an outer cylindrical casing 4 with a gap 14 provided within the casing and is retained by { TAIL ~ a pair } of { HEAD ~ front and rear shielding plates } 17 and 18
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH