Double-stracture tube

A double-structure tube, comprising:

• an exterior having an engage member;
• a pump member, which includes an external cylinder having a first discharge outlet at one end and the inner cylinder having a second discharge outlet at one end wherein the external cylinder and the inner cylinder are connected to each other at their other ends, respectively, and wherein the inner cylinder is placed in the exterior and the external cylinder is exposed;
• a lid, which is formed with the pump member integrally, for covering the first discharge outlet;
• and
• a built-in balloon, which is coupled to the pump material for plugging the second discharge outlet, the engaging member is detachably engaged with the pump member, and wherein, the built-in balloon is placed in the exterior.