Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means designed to produce a jet, spray, or other discharge of particular shape or nature, e.g. in single drops, {or having an outlet of particular shape} in flat form, e.g. fan-like, sheet-like {having a flow conduit with, immediately behind the outlet orifice, an elongated cross section, e.g. of oval or elliptic form, of which the major axis is perpendicular to the plane of the jet}