A small pore size is used and the grid has {TAIL ~ a thickness} chosen to provide {HEAD ~ high scatter rejection} 
A small pore size is used and the grid has { TAIL ~ a thickness } chosen to provide { HEAD ~ high scatter rejection }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD