{HEAD ~ Each module} has {TAIL ~ a housing} divided by walls into a transfer chamber at one end and a second chamber at the other end 
has
{ HEAD ~ Each module } has { TAIL ~ a housing } divided by walls into a transfer chamber at one end and a second chamber at the other end
HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH