Abstract: A self-sealing paste discharge device for dispensing semi-liquid substances especially such as are contained in a collapsible tube in which there is an elastic neck having an elastic closure slitted, the neck presenting a helical path to the slitted closure end so that when paste under pressure is forced through the helical path of the neck, pressure on the opposite sides of the path will open the slit or slits in the closure for the discharge of the paste therethrough, the relationship of the relative elasticity of the neck and closure to the viscosity of the paste being such that when the pressure on the paste is released, the parts on either side of the slit will come together and seal the discharge path.