{HEAD ~ a control ring} having {TAIL ~ a wall} with an inside and outside surface, said control ring rotatably fitted into said housing cavity, said control ring having a vent in said wall, said vent communicating with said outlet port 
having
{ HEAD ~ a control ring } having { TAIL ~ a wall } with an inside and outside surface , said control ring rotatably fitted into said housing cavity , said control ring having a vent in said wall , said vent communicating with said outlet port
HEAD 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 OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH