The restricting apparatus includes {HEAD ~ a member} having a first surface, {TAIL ~ a second surface} opposing the first surface and an opening between the first and second surface for restricting the fluid flow therethrough 
The restricting apparatus includes { HEAD ~ a member } having a first surface , { TAIL ~ a second surface } opposing the first surface and an opening between the first and second surface for restricting the fluid flow therethrough
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH