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