Two motor compressor units of {TAIL ~ the vertical shaft type} are housed in spaced parallel relation in {HEAD ~ a common sealing housing} 
Two motor compressor units of { TAIL ~ the vertical shaft type } are housed in spaced parallel relation in { HEAD ~ a common sealing housing }
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD