Abstract: Multiple embodiments of fluid flow control valves are disclosed to include a plurality of unique features including; an operating spindle mounted within the valve casing to provide protection for both the spindle and valve stem, means for indicating the position of the valve stem, e.g. a dial guage mounted directly on the stem or a two-stage scale mounted on the stem and on the valve operating spindle, a stem structure which accommodates flow path sizing as well as positive no-flow sealing without the use of soft seals, adjustment structure which eliminates tolerance problems resulting from manufacturing, and replaceable flow control apparatus to permit use of a single basic valve to provide flow control in a wide range of circumstances.