{HEAD ~ High vacuum}, which indicates minimal gas consumption, increases {TAIL ~ the size} while low vacuum, which indicates increased gas consumption, decreases the size 
{ HEAD ~ High vacuum } , which indicates minimal gas consumption , increases { TAIL ~ the size } while low vacuum , which indicates increased gas consumption , decreases the size
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH