{HEAD ~ The system} also includes {TAIL ~ a pressure differential switch} which senses a drop in pressure across a pedal valve 
includes
{ HEAD ~ The system } also includes { TAIL ~ a pressure differential switch } which senses a drop in pressure across a pedal valve
HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH