- cast-iron monoblock construction from 1 to 7 working sections.
- parallel circuit, load check valve protection on down-stream of the pressure "P" line.
- tandem circuit, only the first working section, l.c.v. protection + l.c.v. protection on down-stream of the "P" line.
- possibility of power beyond.
- several types of spool: double, single acting, spool motor, float position, regenerative position etc.
- several spool control devices and spool positioning devices.