{HEAD ~ A more specific object} of the present invention is to provide {TAIL ~ a bi directional flow control valve} with substantially identical flow control characteristics in opposite flow directions 
is to provide
{ HEAD ~ A more specific object } of the present invention is to provide { TAIL ~ a bi directional flow control valve } with substantially identical flow control characteristics in opposite flow directions
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH