A two circuit master cylinder unit 1, wherein said means urging said enlargement into a normal middle position comprises {HEAD ~ spring means} disposed in said cavity and engaging {TAIL ~ said enlargement} 
engaging
A two circuit master cylinder unit 1 , wherein said means urging said enlargement into a normal middle position comprises { HEAD ~ spring means } disposed in said cavity and engaging { TAIL ~ said enlargement }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL