with hydraulically-operated opening means; with arrangements for pressure relief before opening

Full Title

Fluid-delivery valves, (for liquid handling B67D; for flushing devices for water-closets or the like E03D) > Self-closing valves, i.e. closing automatically after operation > in which the closing movement, either retarded or not, starts immediately after opening > with hydraulically-operated opening means; with arrangements for pressure relief before opening