The apparatus 4, wherein {HEAD ~ the projecting part} is integrally formed with {TAIL ~ a main body} of the mask 
The apparatus 4 , wherein { HEAD ~ the projecting part } is integrally formed with { TAIL ~ a main body } of the mask
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH