Abstract: A special tube with a retainer, said tube accommodated inside a special container and designed as a device for extracting liquid from the container wherein it is accommodated. Said retainer, said tube and a cap are designed in such a way that said container wherein the tube is located can be closed and opened, so that the tube will contract or release. The cap is specially adapted for the bottle with the tube, said cap having a free cavity in the upper portion thereof for accommodating the upper end of the tube when the bottle with the tube is closed, said cap also having a inner protrusion for leakproof closing of the bottle.